GAME OVERVIEW

Players work to build underwater cities, a transportation network that connects them, and various facilities that support them. In each round, players take turns choosing an action while simultaneously playing a card. If the card matches the color of the chosen action slot, the player also gains a benefit from the card.

At three times during the game, players will deal with Production, a special phase in which their underwater network produces points and resources while their people consume food. At the end of the game, additional points are awarded for various accomplishments and the player with the most points wins.

COMPONENTS

1

double-sided main game board

4

4 player info cards

4

4 double-sided player boards

4

4 final scoring cards

4

4 personal assistant cards

3

action tiles in each of 4 player colors

66

cards in the era 1 deck

57

cards in the era 2 deck

57

cards in the era 3 deck

10

three-credit special cards

15

one- and two-credit special cards

8

government contract cards

11

blue metropolis tiles

5

brown metropolis tiles

20

1-Credit tokens

10

5-Credits tokens

5

10-Credits tokens

12

1-biomatter tokens

5

3-biomatter tokens

19

1-kelp tokens

8

3-kelp tokens

19

1-steelplast tokens

8

3-steelplast tokens

15

1-science tokens

6

3-science tokens

46

double-sided tunnel tiles

1

action-cloning tile

4

multiplier tiles

17

nonsymbiotic city domes (white)

13

symbiotic city domes (purple)

je 3

markers in each in each of 4 player colors

1

era marker

37

farm tokens

37

desalination plant tokens

37

laboratory tokens

GAME SETUP

1 Place the main game board in the center of the table. The board is two-sided. The side shown here is used for a 3 or 4-player game. Use the other side for a 2-player game.

2 The various components that represent cities, tunnels, buildings, and resources should be kept in a common supply. If necessary, you can keep the supply in two places so that everyone can reach the components easily.

3 Cards with divers on the back are separated into 3 decks, one for each era of the game. The Era II and Era III decks can be set aside right now. Shuffle the Era I cards face down and place the deck on the main game board, as shown. Note: Thorough shuffling is very important for this game. You don’t want same-colored cards to be clumped together.

4 Place the era marker on the starting space of the era track.

5 Place one score marker for each player on the zero space of the scoring track.

6 SPECIAL CARDS

Special cards represent specialists you can hire for your underwater endeavors. Each has a cost near the upper left corner.

Separate the Special cards into two groups:

A group that costs one or two credits.
A group that costs three credits.

Shuffle the deck of one-or-two-credit Special cards and place it on the main board. Turn the top card face up.

Shuffle the three-credit Special cards and deal 6 face up to the corresponding spaces in the center of the game board. Return the rest of the three-credit deck to the box. These 6 are the only three-credit Special cards that will be available during this game.

SETUP FOR 2 OR 3 PLAYERS

When setting up the game for fewer than four players, make two changes:

Leave the action-cloning tile in the box.
Use fewer symbiotic cities (purple domes):
1. With two players, use 7 symbiotic cities.
2. With three players, use 10.

A four-player game uses the action-cloning tile and all 13 symbiotic city domes.

PLAYER SETUP

Each player chooses a color and takes the 3 action tiles, the Personal Assistant card and final scoring card in that color. Although the Personal Assistants have different illustrations, they all have the same effect.

Each player should also take a player info card.

Each player starts with 1 kelp, 1 steelplast, 1 science, and 2 credits.

(Some players may get additional resources once order of play has been determined.)

>> PLAYER BOARD SETUP

Each player takes a different player board, chosen at random. Your nation’s infrastructure begins with a city in the lower right corner of your board. There are two types of cities – symbiotic and nonsymbiotic. Your starting city is a nonsymbiotic city represented by a white dome, as shown.

Separate the brown hexagonal metropolis tiles from the blue ones. Mix up the brown ones and randomly give one to each player. Then mix up the blue ones and randomly give two to each player.

Your brown metropolis goes on the hexagonal space in the upper left corner. The other two should be randomly assigned to the remaining two spaces.

The player boards are two sided. For your first game, use the side depicted above (# 1-4, ☆). Later, for more variety, you can try the other side, which has more asymmetry (# 5-8, ☆ ☆ ☆).

>> PLAYER CARDS (CARDS FOR THE FIRST ROUND)

At the start of the game, you draw 6 cards from the Era I deck. Choose 3 to keep, and discard the other 3.

If you are new to the game, try to keep one card of each color. And don’t worry about this decision too much – every card offers interesting choices, and you will be getting more cards very soon.

ORDER OF PLAY

Two tracks determine the order of play. The play-order track shows the order of play for the current round. The Federation track is where players jockey for position for the next round.

For the first round, place the play-order markers on the play-order track randomly; on the Federation track the markers should be placed in the opposite order. Those who play third and fourth get additional resources.

In later rounds, play order and initial position on the Federation track will be determined differently.

Two tracks determine the order of play. The play-order track shows the order of play for the current round. The Federation track is where players jockey for position for the next round.

For the first round, place the play-order markers on the play-order track randomly. Then, on the Federation track, the markers should be placed in the opposite order, as shown, and those who play third and fourth get additional resources. Specifically:

The player on space 1 of the play-order track will play first in the first round. On the Federation track, his or her marker will start below the track, on the space with the matching color.
The player on space 2 plays second. His or her other marker will start on space 4 of the Federation track.
The player on space 3 will also start on space 3 of the Federation track and will start with one extra credit.
The player who plays last will start on space 2 of the Federation track and will start with 1 credit and 1 steelplast in addition to the usual starting resources.

The first round is the only round that starts this way. In later rounds, play order and initial position on the Federation track will be determined differently.

GAME PLAY

Players take turns by choosing one card to play and one unused action slot (preferably the same color as the card, otherwise the card is discarded). The chosen action slot is marked with the player's action tile.
At the end of your turn, you always draw 1 card.
After 3 turns, the round is over and the era marker advances one space. Possibly a production phase will follow.

Here is a quick summary of how the game is played:

>> PLAY ORDER

Players take turns choosing actions. They play in the order depicted on the play-order track, and this order does not change during the round.

>> A TURN

You always start your turn with 3 cards. On your turn, you play one card and simultaneously choose one of the available action slots . That is, you choose a slot that no one else has chosen this round. (There is also a special slot, explained later, that is always available.) You place one of your action tiles on the slot to indicate that you have chosen it. This makes the slot occupied and not available for the rest of the round.

If the color of the card you played matches the color of the slot you chose, you also get to perform the card’s effect. If the color does not match, you just take the action and discard the card with no effect – you assigned some personnel to the job, but it was not their area of expertise, so they just did the job without accomplishing any additional tasks.

At the end of your turn, you always draw 1 card. It’s also possible to draw additional cards as part of an action or card effect. If you end up with more than 3 cards, you will have to discard down to 3. You may discard any time before you take your next turn.

Adaptation for the online game: The cards which you draw during your turn will be shown to you after you have finished your turn. You can discard down to 3 at the beginning of your next turn.

>> A ROUND

Players continue until each has taken 3 turns. As cards are played, slots will be occupied, making them unavailable for those who play later in the round. The number of available slots will diminish. When everyone has taken 3 turns, it is the end of the round. The end of the round is described in detail here.

>> THE ERA MARKER

At the end of each round, the era marker advances one space along the era track. When it reaches a Production space, there is a Production phase.

>> PRODUCTION

During Production, your underwater network will produce various resources. At the end of Production, each of your connected cities will consume 1 kelp. Details are here.

>> AN ERA

An era consists of 4 rounds in Era I and 3 in Era II and Era III. The end of each Production phase marks the end of an era. New cards will come into play, as explained here. The game has a different deck of cards for each era. At the end of Era III, the game is done.

>> FINAL SCORING

At the end of the game, players score various aspects of their underwater network, and the player with the most points wins.

CARDS

>> GENERAL INFORMATION

Each turn you play one of your hand cards.
If the color of the card matches the color of the chosen action slot, then you get to resolve the card before or after performing the action (if it has an immediate effect) or play the card in front of you (if it is a different card type).
If the color does not match, the card is discarded.

The cards in your hand represent personnel you have at your disposal. On each turn, you will play one of these cards as you choose that turn’s action. This represents sending your personnel out to complete that assignment.

You begin each turn with exactly 3 cards. During your turn, you play exactly 1 of these, while simultaneously choosing an action slot.

If the color of the card does not match the color of the slot, then you ignore the card and just perform the action. However, if the color matches, then you get to resolve the card before or after performing the action.

The three colors have different power levels:

Green cards are the strongest, but you get their benefits only when you play them on green action slots, which are the weakest.
Red cards and action slots have a moderate power level.
Yellow cards are the weakest, but the yellow action slots are the strongest.

Some cards have an instant effect. All others can be claimed for later use, as explained below. All five types of cards are described in this section.

>> INSTANT EFFECTS

Resolve the card’s effect immediately before or after you perform your chosen action.

When you play a card with this symbol, if its color matches your chosen action slot, you resolve the card’s effect immediately before or after you perform your chosen action. If the color does not match, you ignore the card’s effect.

In either case, these cards are discarded to the discard pile on the main board.

>> CLAIMING CARDS

Cards without immediate effect are placed near your player board.

Four types of cards do not have instant effects. When you play such a card, if its color matches your chosen action slot, you claim the card by placing it near your player board. It thus becomes a permanent part of your underwater nation.

If the color of the card does not match the color of the slot, you cannot claim the card. It goes to the discard pile.

>> PERMANENT EFFECTS

Permanent effects can be triggered whenever a certain event happens, or give you a discount in certain situations, or offer a special ability that you can use every turn. Permanent effects can be used as soon as the card is claimed.

Cards marked with this symbol have a permanent effect. You gain the card’s benefit if you claim it, as described above. Permanent effects take various forms. Some permanent effects trigger whenever a certain event happens. Others might give you a discount in certain situations. Some offer a special ability that you can use every turn.

It is legal to use the permanent effect even on the turn in which you claim the card.

>> ACTION CARDS

To use an action card, you must use an action slot or a card effect that allows you to do so. It is legal to use an action card even on the turn in which you claimed it. Each action card is limited to one use per era. You are limited to 4 action cards. If you already have 4, then you must discard one before you claim a new action card. You may use the discarded card one more time (if it has not been used yet).

Cards with this symbol are action cards. Your claimed action cards offer additional actions your underwater nation can perform. To use an action card, you must use an action slot or a card effect that allows you to do so.

EXAMPLE:

If you choose this action slot, you may use one of your action cards and gain 1 steelplast.

EXAMPLE:

If you play this instant-effect card on a green slot, you may use one of your action cards before or after performing the slot’s action.

It is legal to use an action card even on the turn in which you claimed it.

Each action card is limited to one use per era. After use, rotate it 90 degrees to the right to show that it has been used and is no longer available. At the end of the era, after Production, all action cards are restored to the usual orientation to show that they will be available again in the new era.

Note: There are a few instant-effect cards which allow you to make an used action card available again. This can allow you to use an action card more than once in the same era.

>> LIMIT OF FOUR

You are limited to 4 action cards (and your Personal Assistant [see on the top] counts as one of the 4). If you already have 4, then you must discard one before you claim a new action card. The discarded card can be one that has been used this round or one that is still available.

If you make room for a new action card by discarding one that is available, you may immediately use the discarded action. It is as though your new action card also came with an instant effect that lets you use the discarded available action card.

PERSONAL ASSISTANT

During setup, each player received a Personal Assistant. This is an action card that is already claimed and in play at the beginning of the game. It follows the same rules as any other action card. When you use the action, you decide whether to gain 1 steelplast or 1 credit.

It could also be discarded within the “Limit of four” rule.

>> PRODUCTION CARDS

Your claimed production cards take effect during the Production phase, which happens three times during the game.

Cards with this symbol are production cards. Your claimed production cards take effect during the Production phase, which happens three times during the game. Some produce resources directly. Others may modify your production based on what is connected to your network.

>> END-SCORING CARDS

Your claimed end-scoring cards can give you points at the end of the game.

Cards with this symbol are end-scoring cards. Your claimed end-scoring cards can give you points at the end of the game. Some give you points based on some aspect of the network you have built. Others may allow you to convert certain resources to points.

Details of particular card effects can be found here.

>> SPECIAL CARDS

The only way to get a Special card is to use a specific action slot. Special cards cost between 1-3 credits when played; these costs can be seen in the left upper corner of the card. Special cards with an immediate effect are kept under your player board after performing the effect. Likewise for Special cards with action symbol which are discarded due to the "limit of 4" rule.

The cards you draw from the regular deck are unknown to you until you draw them. But some cards start the game face up for all to see. These are called Special cards.

Special cards cannot be drawn in the usual way. The only way to get one is to use the action slot marked like this.

This action is explained here.

The Special card remains in your hand. It can be played just like any other card. If it does not match your chosen action slot, then it is discarded and returned to the bottom of the Special card deck with no effect. If it matches, then it has an effect only if you pay the cost depicted near the upper left corner.

EXAMPLE:

The player must pay 3 credits to play this card if she wants its special benefit.

DISCARDING SPECIAL CARDS

When one- or two-credit Special cards are discarded (for example, when you are discarding down to your hand limit) they should be immediately returned to the bottom of the Special card deck.

When you play a one- or two-credit Special card:

If the color does not match the chosen action slot, return the card to the bottom of the Special card deck.
If you choose not to pay to play the Special card, return it to the bottom of the Special card deck.
If the color matches and you pay to play it, then you keep it. If it has an instant effect, keep it under your player board after performing the effect to ensure that it will not re-enter play. If it is not an instant-effect card, claim it in the usual way.

Three-credit Special cards have no way to re-enter play. Generally, they are too valuable to discard, but if one is discarded, you can return it to the box.

Cards are discarded to the discard pile. Discarded cards of earlier eras should be put back into the deck of this era.

ACTION SLOTS AND CARD EFFECTS

It is legal to use only part of an action or card effect. However, you are not allowed to choose an action slot without using at least part of its effect.

On your turn, you choose an action by placing one of your action tiles on an action slot. Slots that have already been chosen this round are occupied and cannot be chosen again. Slots that have not yet been chosen are available.

The two sides of the main board have different action slots. One side is designed for a two -player game. The other side is designed for three or four. A key for action slots of each board can be found here.

When you place your tile on an action slot, you must also play a card from your hand. The action slots and the cards come in three colors. If the color of your card matches the color of the action slot, you may resolve the card’s effect before or after you perform the slot’s action. If the colors do not match, you ignore the card and only perform the slot’s action.

It is legal to use only part of an action or card effect. For example, if an action slot allows you to build a city and a tunnel, you can choose to build only the tunnel, if you wish.

However, you are not allowed to choose an action slot without using at least part of its effect. For example, if you do not have enough resources to build 1 tunnel, you cannot choose the action slot that allows you to build 2 tunnels.

Card effects are always optional, so it is legal to play a matching card and not use its effect at all.

In this section we will illustrate core gameplay concepts with action slots, but these rules also apply to many of the card effects as well.

>> RESOURCES

Underwater Cities has many resources that players can gain or spend. The gaining of a resource is represented by a simple icon:

	Gain 1 steelplast.		Gain 1 credit. That is, take a 1-credit token from the supply and keep it near your player board.
	Gain 1 kelp.		Gain 1 card. That is, draw a card from the current era’s deck. Do not take any of the Special cards from the board.
	Gain 1 science.		Gain 1 point. Advance your point marker one space on the scoring track.
	Gain 1 biomatter.

In general, credits, science, kelp, steelplast, and biomatter are used to pay costs. Kelp is also used for feeding your people (there are other ways to feed people, but kelp is the most efficient). Cards, of course, are useful because they give you more choices on your turn. And points are how you win the game. So anything you gain is sure to be useful to you sooner or later.

EXAMPLE:

The player who chooses this action slot will take 2 steelplast tokens and 1 kelp token from the supply and keep them near his or her player board.

You can organize your claimed cards by type. The icons on top allow you to lay them out compactly, as shown.

LIMITED AND UNLIMITED COMPONENTS

Credits, kelp, steelplast, science, and biomatter tokens are not intended to be limited. If the supply runs low, you can use higher denominations and the multiplier tiles to represent the amount of resources you have. You can make change freely at any time.
Building tokens are not intended to be limited. If you run out of a particular type, you can usually substitute a different colored token. For example, if players have lots of upgraded farms, the supply might run out of green tokens. You can get more in the supply by replacing the bottom tokens of some upgraded farms with a color you have lots of. The green token on top is sufficient to remind you that it is an upgraded farm.
Tunnels and nonsymbiotic cities are limited. The supply starts with 46 tunnels. When they are gone, no one can build tunnels anymore. Similarly the game has only 17 nonsymbiotic city domes, and no more than this may be built.
Symbiotic cities are limited. The limit depends on the number of players:
- In a two-player game, use 7 symbiotic city domes.
- In a three-player game, use 10.
- In a four-player game, use all 13.
The era deck is not limited. If it runs out of cards, shuffle its discard pile to make a new deck.
You should not run out of one- or two-credit Special cards. Whenever these are “discarded” they return immediately to the bottom of the deck.
Three-credit Special cards are limited. Only six are available in the game.

>> CITIES

Pay 2 steelplast, 1 kelp and 1 credit for a nonsymbiotic city (white dome);
Pay 1 steelpast, 1 kelp, 1 biomatter and 2 credits for a symbiotic city (purple dome).
The site you choose for your new city must be adjacent to an existing city.

Cities provide the habitat for the people of your underwater nation. At the end of the game, every city connected to your network will be worth points. There are 2 types of cities.

Build a city:

City type	costs

Pay 2 steelplast, 1 kelp and 1 credit for a nonsymbiotic city (white dome);

or pay 1 steelpast, 1 kelp, 1 biomatter and 2 credits for a symbiotic city (purple dome).

When you build a city, pay the usual cost and take the corresponding dome from the supply. Place the dome on an empty city site on your player board. The site you choose for your new city must be adjacent to an existing city. In other words, the new city must have a tunnel site that could connect it to an existing city. It is legal to build new cities before building the connecting tunnels.

Symbiotic cities are a little more expensive (biomatter is difficult to get) but they can produce points during Production. Nonsymbiotic cities are a little easier to build (if you have the steelplast) but they do not produce points. Both kinds of cities can give you points at the end of the game, and both require kelp to feed them at the end of Production. Whenever a rule or effect applies to a city, that means “a symbiotic or nonsymbiotic city.”

>> BUILDINGS

Build a farm. This costs 1 kelp.
Build a desalination plant. This costs 1 credit.
Build a laboratory. This costs 1 steelplast.
The site you choose for your new building must be adjacent to an existing city or adjacent to a site on which you could build a new city.
You can build on Expansion Sites (dashed circle and darker background) only if you play a card with an effect that specifically allows that.

Buildings are special facilities that help to make your underwater nation self-sufficient. You can build 3 types of them:

Building type	cost

Build a farm. This costs 1 kelp.

Build a desalination plant. This costs 1 credit.

Build a laboratory. This costs 1 steelplast.

When you build a building, pay the cost (which is depicted on your player info card) and take a token of the corresponding color from the supply. Place the building token on an empty building site. The site you choose for your new building must be adjacent to an existing city or adjacent to a site on which you could build a new city.

The different buildings produce different things during Production. They will produce more if they are upgraded (upgrades are explained here). Also, certain cards may have a conditional effect that only applies if you have certain buildings. Buildings have none of these beneficial effects until they are connected to your network. To connect them, you will need to build tunnels and cities. See YOUR NETWORK.

EXPANSION SITES

Each city has an additonal building site that is generally off limits. You can build on this site only if you play a card with an effect that specifically allows you to build on an expansion site (and only if it is adjacent to an existing city or a site on which it is legal to build a new city).

>> TUNNELS

Build a tunnel. This costs 1 steelplast and 1 credit.
The site you choose for your new tunnel must be connected to your starting city.

Tunnels connect your cities to your underwater network.

Tunnel	cost

Build a tunnel. This costs 1 steelplast and 1 credit.

When you build a tunnel, pay the cost and take a tunnel tile from the supply. Place it on a tunnel site with the non-upgraded side up. The tunnel in the illustration above is non-upgraded.

The site you choose for your new tunnel must be connected to your starting city. Tunnels are connected if you can trace a path along the tunnels back to your starting city. The path can go through cities or through empty city sites, but not through empty tunnel sites.

COSTS

The usual cost for building a city, building, or tunnel is depicted on your player info card. This is the cost you pay when you build something by choosing an action slot.

Certain card effects also allow you to build things. If the card does not specify a cost, you pay the usual cost. However, if the card specifies a cost, you pay that cost instead of the usual cost.

STEP-BY-STEP EXPANSION

You build your tunnels, buildings, and cities one-at-a-time. For example, if you choose this action slot, you first build one tunnel on a legal tunnel site and this could open up one or more new legal sites for the second tunnel.

>> YOUR NETWORK

A city is connected to your network if there is a chain of tunnels from it to your starting city.
A building adjacent to a connected city is connected to your network.
Buildings and cities that are not connected do not produce during Production. They do not consume kelp at the end of Production. They do not count during final scoring.

We have seen that tunnels must be connected to your starting city, but buildings and cities do not have to be. This gives you freedom in how you choose to expand. However, you eventually want everything on your board to be connected to your network.

Your network is all the structures and cities and empty city sites that are connected to your starting city:

By definition, your starting city is always connected to your network.
All your tunnels are automatically connected to your network because building a tunnel that is disconnected is not legal.
A city is connected to your network if there is a chain of tunnels from it to your starting city. Because all your tunnels are connected, any city with a tunnel leading to it is connected and a city with no tunnels is not connected.
A building adjacent to a connected city is connected to your network.

Buildings and cities that are not connected do not produce during Production. They do not consume kelp at the end of Production. They do not count during final scoring.

=

/

Biomatter is a remarkable substance, somewhat more rare than the other resources. In addition to being essential for building symbiotic cities, biomatter can also be a universal building material. Only when building a tunnel, building, or city, any part of the cost that requires kelp or steelplast can be paid with biomatter instead.

EXAMPLE

A nonsymbiotic city normally costs 2 steelplast, 1 kelp, and 1 credit. But you could build it with 1 steelplast, 2 biomatter, and 1 credit.

>> UPGRADING STRUCTURES

Whether upgrading a tunnel, a farm, a desalination plant, or a laboratory, the usual cost is 1 science. However, the card effects offer you special cost opportunities.
An upgraded tunnel still counts as a tunnel, an upgraded farm still counts as a farm, etc.
Upgraded structures produce more during Production, and certain cards may provide benefits for having upgraded structures.

Buildings and tunnels are called structures in this game. Structures are different from cities in that structures can be upgraded. There is a card that will let you turn a nonsymbiotic city into a symbiotic city, but this is an exception.

To upgrade, you need a card or action slot with a depiction like this:

Upgrade structure	cost

Upgrade 1 structure. Pay 1 science.

Whether upgrading a tunnel, a farm, a desalination plant, or a laboratory, the usual cost is 1 science. However, the card effects offer you special cost opportunities.

When you upgrade a building, take the corresponding token from the supply and stack it atop the structure you are upgrading. To upgrade a tunnel, flip the tile over to the upgraded side.

An upgraded tunnel still counts as a tunnel, an upgraded farm still counts as a farm, etc. It is not possible to upgrade any structure that is already upgraded.

Upgraded structures produce more during Production, and certain cards may provide benefits for having upgraded structures.

>> THE FEDERATION TRACK

When an action slot or card effect allows you to advance 1 space on this track, move your marker 1 space ahead.
If there is a bonus depicted beside that space, immediately gain the depicted resource.
If you move ahead more than 1 space, gain the bonus of each of those spaces.
If you advance when you are already on space 1, put your marker atop any others on space 1 and score 1 point for each space you were supposed to advance.

We have explained how to build your underwater nation, but you also need to build a good reputation with the world government! You do that by choosing actions or playing cards with this symbol:

Advance 1 space on the Federation track.

Before the first round, players’ markers are placed on separate spaces of the Federation track in reverse play order, as explained here. At the beginning of subsequent rounds, the markers begin below space 4, as explained here.

When an action slot or card effect allows you to advance 1 space on this track, move your marker 1 space ahead. If there is a bonus depicted beside that space, immediately gain the depicted resource. If you move ahead more than 1 space, gain the bonus of each of those spaces.

If your marker ends up on an occupied space, place it atop the other markers which are already there (being atop other markers means you will play ahead of them in the next round).

Even when you have advanced as far as possible, you can still gain benefits from “advancing” more. If you advance when you are already on space 1, put your marker atop any others on space 1 and score 1 point for each space you were supposed to advance.

>> DRAWING SPECIAL CARDS

Take one of the three-credit Special cards.
Or take the top card from the deck (the one-or-two-credit deck) and turn the next card face up.
Or turn the top card face down, move it to the bottom of the deck, and draw the next 3 cards. Choose one of these 3 to keep and return the other 2 to the bottom of the deck in either order. Then turn up the new top card.

This symbol indicates that the action slot allows you to take a Special card. Many Special cards are available face up in the center of the game board.

When you take a Special card, you either:

Take one of the three-credit Special cards (it is not replaced).
Or take the top card from the deck (the one-or-two-credit deck) and turn the next card face up.
Or turn the top card face down, move it to the bottom of the deck, and draw the next 3 cards. Choose one of these 3 to keep and return the other 2 to the bottom of the deck in either order. Then turn up the new top card.
Once a Special card is in your hand, it is mostly like any other card. The differences are discussed here.

>> USING ACTION CARDS

You may use 1 of your action cards.

Action cards are a certain type of card you claim and keep near your player board. They have actions which can be used during the game, but only when you use an action slot or a card effect with this symbol:

You may use 1 of your action cards. The rules for using action cards are here.

>> THE ALWAYS-AVAILABLE SLOT

The always-available slot allows you to gain 2 cards and 2 credits, and you discard your hand card.

One action slot is always available, even if another player has already chosen it this round. It has no color, so when you choose it you ignore the effect of the card you play.

The always-available slot allows you to gain 2 cards and 2 credits.

Note: Some Special card effects allow you to use the action depicted at an action slot. These effects apply only to the colored slots, not to the always-available slot.

>> THE ACTION-CLONING TILE (4 PLAYERS)

Pay 1 credit to choose an action slot occupied by another player.
Once the action-cloning tile is used, it cannot be used again for the rest of the round.

In a four-player game, the important action slots become occupied quite quickly. The action-cloning tile (which is available only in a four-player game) gives players a second chance at one of these slots.

On your turn, instead of choosing an available action slot, you may do the following:

Pay 1 credit.
Take the action-cloning tile.
Choose an action slot occupied by another player.

Your action tile goes on the slot you chose, on top of the other player’s tile. You also play a card, as usual, and you gain the benefits of the card if its color matches the chosen slot. Note that you cannot choose a slot that is already occupied by your tile.

Note on card effects: In a four-player game, “any slot occupied by another player” actually means “any occupied slot not occupied by you”. The idea is that if you have already placed a tile on that slot, a card that allows you to use “any slot occupied by another player” will not allow you to use that slot again. So a slot occupied by you and another player does not count as a “slot occupied by another player”.

>> ONE-TIME USE

Once the action-cloning tile is used, it cannot be used again for the rest of the round. The player who used the tile keeps it as a reminder that this option is no longer available. The tile is returned to its place on the main board at the end of the round.

>> SUMMARY OF CHOOSING AN ACTION SLOT

Choose an unoccupied action slot.
Play a card from your hand.
If the color of the card does not match, discard the card with no effect.
Otherwise resolve the card’s effect either before or after performing the action.

Place one of your action tiles on an unoccupied action slot or on the always-available slot.
Play a card from your hand.
If the color of the card does not match the color of the slot, perform the action and discard the card with no effect. The always-available slot has no color and cannot be matched.
If the color of the card matches, then you choose one of these:
1. Either perform the action, and then resolve the card’s effect.
2. Or resolve the card’s effect first, and then perform the action.

TIMING

Some effects have multiple parts. The parts of an effect can be resolved in any order.

This action allows you:

Use one of your action cards
Build a structure for its usual price
Pay 1 science to upgrade just built structure

We have already mentioned this action and it means, that you may build any structure for its usual price and then to upgrade it immediately by paying 1 science. In addition you can use one of your action cards. According to the order of playing individual parts of this action, you can first use an action card which gives you for example 1 credit and then you can pay this credit and 1 science to build and immediately upgrade desalination plant.

Be careful!! You must resolve all card effects and then all actions from an action slot or vice versa. Resolving these 2 sets of actions simultaneously is not allowed.

EXAMPLE

Suppose, that you have card with permanent effect no. 37 and action card no. 34 and you decide to play a card to the red action slot described above. In your supply you´ve got 1 steelplast and 1 science. You don´t have any credits, but you would like to build a desalination plant. Here is the description of how to do this with the resources and cards you have. First of all, pay 1 steelplast and build a laboratory. You have built your laboratory to a connected city and it is the second one, so because you claimed card no. 37 before you gain 1 credit immediately. Then you have to pay 1 science and upgrade the laboratory you´ve just built (the whole action has to be performed i.e. “build and upgrade” not just “build” or just “upgrade”) . Now you can resolve the other part of the action slot that allows you to use one of your action cards . You will pay 1 credit, which you´ve gained to build a desalination plant. And then you draw a card.

In this case there are two limitations with regard to resolving effects:

If a new effect triggers, resolve it immediately, even if you haven’t finished the effect which triggered it (as with card no. 37 above).
You have to resolve a card effect and the action of the chosen action slot separately and completely before resolving the other.

EXAMPLE

Kate chooses this red action and plays this red card no. 28. She also has this action card no. 19, which she claimed on an earlier turn.

Suppose she has 1 steelplast, 1 credit, 1 science, no kelp, and no upgraded tunnels. She is on space 4 of the Federation track.

The Seafood Collection effect is of no use to her until she has an upgraded tunnel, so she decides to resolve the action slot first. The action slot allows her to build and upgrade a tunnel. She pays 1 steelplast and 1 credit to build it and 1 science to upgrade it. She can’t use Seafood Collection now because she has not completely resolved the action slot’s effect.

The other part of the action slot’s effect allows her to use her Build A Structure card. Kate has no resources for building, but she can use the second part of the effect first. Kate advances 1 space on the Federation track. She immediately gains 1 credit (effects on the Federation track are also triggered effects which must be resolved immediately). Now she can spend that credit to build a desalination plant, using the first part of the action card’s effect. Both parts have been resolved, so the action card is resolved. And thus, the entire action slot has now been resolved.

Now, and only now, can she use Seafood Collection. She has an upgraded tunnel, so she gains 1 kelp.

There was no way for her to use this kelp to build a farm instead of a desalination plant. The action slot and all its triggered effects had to be resolved completely before she could use her card.

Of course it would have been legal to use the Seafood Collection card before considering the action slot. In Kate’s situation, it would have been useless, but if she had already built an upgraded tunnel on an earlier turn, she could have gained the kelp before resolving the action slot.

Also it would have been legal to forgo using the action card Build A Structure, and only use the "build and upgrade" a structure effect of the action slot.

BONUSES FROM BUILDING

Your player board depicts certain bonuses you may gain from building. Every board offers different bonuses. When you build a structure or a city on a site marked with a resource, you gain the resource.

Building on a site marked with this symbols allows you to advance 1 space on the Federation track and draw one card from the current Era deck.

You gain the bonus even if the city or building you build on that site is not yet connected to your network. These bonuses are triggered effects, which are resolved immediately, even in the middle of an action:

EXAMPLE

Suppose you can legally build on a tunnel site which provides 1 steelplast as bonus. You choose the action that allows you to build 2 tunnels. You pay 1 steelplast and 1 credit to build on this site and immediately gain 1 steelplast. You may use this steelplast (and 1 more credit) to build your second tunnel.

>> METROPOLISES

You gain benefits from expanding your network out to connect with metropolises.
To connect to a metropolis, you need to build all tunnels on the adjacent tunnel site (1 or 2).
Your brown metropolis can give you points during final scoring.
The blue ones have an instant effect and some an additional production effect.

You also gain benefits from expanding your network out to connect with coastal metropolises.

To connect this metropolis, you need to build a tunnel on the adjacent tunnel site.

To connect this metropolis, you need to build tunnels on both adjacent tunnel sites.

The metropolis tiles offer various benefits that apply only if the metropolis is connected. Your brown metropolis can give you points during final scoring. The blue ones either have an instant effect or an instant effect and a production effect.

END OF TURN

At the end of your turn you always draw 1 card. This is in addition to any cards you may have acquired during your turn. Because you played only 1 card, you now have at least 3.

If you have more than 3 cards, you must discard down to 3. However, you can think about this decision while others are playing. Officially, this decision is made at the beginning of your next turn. In practice, it is okay to discard as soon as you have made up your mind.

END OF THE ROUND

Return all action tiles to their owners.
Reorder the play-order markers according to the order of the markers on the Federation track.
Place all Federation track markers on the colored spaces below space 4.
Advance the era marker. If this is the end of the era, there will be a Production phase before the next round.

During the course of one round, each player will get three chances to play a card while choosing an action slot. The action slots will fill up with action tiles. At the end of the round, everything needs to be reset.

Return all action tiles to their owners. 4 players: In a four-player game, the player who took the action-cloning tile should return it to the middle of the table at this time.
Reorder the play-order markers according to the order of the markers on the Federation track. The player farthest ahead on the Federation track will go first next round. The next player will go next, etc. If markers are in a stack, each marker is ahead of any markers below it. Among markers below space 4, relative play order does not change.
Once you have determined the next round’s play order, place all Federation track markers on the colored spaces below space 4.
Advance the era marker. If this is the end of the era, there will be a Production phase before the next round.

Note: Be sure to determine the new play order even if this is the end of the final round. This final order is the tie-breaking order.

PRODUCTION

>> TIMING OVERVIEW

After each era there will be a production phase.
The first era consists of 4 rounds, the second and third era consist of 3 rounds each.

The era marker moves one space on the era track at the end of each round. After 4 rounds, it will move onto a Production space, reminding you that it is time for your first Production phase. The second Production phase happens 3 rounds later. The final Production phase happens 3 rounds after that, just before final scoring. In all, you will play 10 rounds and have 3 Production phases. Each Production phase marks the end of an era.

>> YOUR NETWORK’S PRODUCTION

Every tunnel adjacent to a city and every building in your network will produce something.
Symbiotic cities will produce 2 points!
Upgraded structures will produce more.
Production bonus for having 2 upgraded buildings of the same type at the same city.
For details see the production overview sheet.

All players can handle their Production simultaneously. Every tunnel adjacent to a city and every building in your network will produce something. Upgraded structures will produce more. Symbiotic cities will produce 2 points!

Nonsymbiotic cities have no production of their own, but they are still useful because they connect buildings to your network.

You also gain a slight production bonus when you have 2 upgraded buildings of the same type at the same city.

The production of your network is depicted on your player info card.

EXAMPLE

Each farm next to a connected city produces 1 kelp.

EXAMPLE

If this farm next to connected city is upgraded, it also produces 1 point.

EXAMPLE

If you have at least 2 upgraded farms at the same connected city, they will also produce 1 additional kelp and 1 additional point.

>> THINGS THAT DO NOT PRODUCE

A city will not produce if it is not connected to your network.

A building will not produce if it is not adjacent to a connected city.

A tunnel will not produce if it is not adjacent to a city (a tunnel connecting a metropolis with a Production effect will allow the metropolis to produce, but the metropolis does not help the tunnel produce).

Think of it like this: The connected cities are the places where people can live. It is the people who are doing the productive work. So a disconnected city will not produce because no one lives there – they can’t move in until you complete a tunnel to it. Similarly, a building next to an empty city site or a building next to a disconnected city does not have anyone there to run the operation. And tunnels that are not attached to any of your cities do not see enough traffic to produce.

>> PRODUCTION FROM CARDS AND METROPOLISES

Apply the effects of your production cards and connected metropolises.
Some production cards modify the production of your structures or cities.

If you have claimed any production cards, or if you have connected your network to any metropolises with a production effect, you apply their effects at this time. When evaluating a production effect that depends on your cities or buildings, you always ignore cities and buildings that are not attached to your network.

Some production cards have no production of their own. Instead, they can modify the production of your tunnels, buildings, and cities. Such cards are evaluated when your network produces, and they do not apply to tunnels, buildings, and cities that do not produce.

>> END OF THE ERA

Rotate your used action cards to the usual orientation.
Feed your cities.
Replace the old era’s deck with the deck for the next era.
Each player draws 3 cards from the new era, adding them to any cards already in hand.
Discard hand cards until you have reached your hand limit.

After everyone has resolved all production from all sources, it is time to resolve the end of the era with the following steps:

Rotate your action cards to the usual orientation to show they can be used in the next era (this step is unnecessary at the end of the final era).
Feed your cities (explained here).
Remove the old era’s deck and discard pile from the game. Players keep any cards from that era that they currently have, but no more new ones will be drawn.
Shuffle the next era’s deck and place it on the game board. This is the new draw pile. Each player draws 3 cards from the new era, adding them to any cards already in hand. From this hand of 6 or more cards, choose 3 to keep and discard the rest. (Discarded cards from the new era go to the discard pile. Discarded cards from the previous era should be returned to that era’s deck.) Skip this step at the end of the final era.
Advance the era marker.

Once everyone has discarded down to 3 cards, you are ready to play the next era with the new deck; or if you have completed the third era, you are ready for final scoring.

HAND LIMIT SUMMARY:

You must discard down to 3 cards at the beginning of your turn and at the beginning of each era. At any other time, it is okay to have more than 3.

If a card increases your hand limit by one, then you must discard down to 4 cards at the beginning of your turn and at the beginning of each era. It is still possible that you will start one or more turns with only 3 cards, because this effect only alters the way you discard, not the way you draw.

>> FEEDING CITIES

For each city pay 1 kelp (as replacement 1 biomatter or 3 points, respectively).
Cities that are not connected do not count as cities to be fed.

At the end of Production, each city in your network must be fed 1 kelp (symbiotic cities have the same requirements as nonsymbiotic cities). Return this kelp to the general supply. If you have more cities than you have kelp, you spend all your kelp to feed those you can and then feed the remaining cities according to this chart:

For each unfed city, pay 1 biomatter. If any cities are still unfed, you feed them by paying points – 3 points per city at the end of each Production. If you lose all your points and still have unfed cities, just leave your scoring marker at 0, but it would be extremely unlikely to lose this many points unless you are deliberately trying to do so.

Only cities in your network require food. Cities that are not connected do not count as cities to be fed because they do not have people in them yet.

FINAL SCORING

In addition to the points you score throughout the course of the game, you may score points for the brown metropolis you have connected to or for specific cards you have claimed. And finally, you will score points for your connected cities and for your remaining resources.

Your underwater nation will score points throughout the course of the game, sometimes as the effect of certain cards, and sometimes during Production. At the end of the game, you may score points for a metropolis you have connected to or for specific cards you have claimed. And finally, you will score points for the overall composition of your network and for your resources.

The order of final scoring is depicted on your final scoring card.

>> FINAL-SCORING TILE

The metropolis in the upper left corner of your player board will give you points if you have connected it to your network with both tunnels.

>> END-SCORING CARDS

Cards marked with this symbol can give you points at the end of the game. Some cards reward you for certain accomplishments. Others let you spend resources to buy points. You should spend as much as you can – there is nothing else you can buy, and buying points via a card is always more efficient than keeping the resources and converting them into points after everything else has been scored.

>> SCORING YOUR NETWORK

Your points are based on the number of different buildings next to each connected city:

2 points for a connected city with no buildings.
3 points for a connected city with 1 type of building.
4 points for a connected city with 2 types of buildings.
6 points for a connected city with all 3 types of buildings.

>> SCORING YOUR RESOURCES

Now, many of your remaining resources can be converted to points:

First, sell all your biomatter for 2 credits each.
Then buy 1 point for every 4 credits, kelp, science, or steelplast you spend, in any combination. (For example, 3 kelp and 1 steelplast is 1 point; 1 science, 2 steelplast, and 1 credit is 1 point; etc.)

Leftover resources do not count. Convert all that you can, and ignore the remainder.

WINNING THE GAME

Whoever has the most points wins. If there is a tie, break the tie according to the tie-breaking play order that was determined at the end of the final round (politics pays).

But regardless of who has the most points, take the time to appreciate the extensive network of underwater cities you have built. Because of your efforts, millions of people now have food, water, and shelter. Great work!

FREQUENTLY OVERLOOKED RULES

Players sometimes overlook the following details:

The number of symbiotic city domes available in the game depends on the number of players – two players, 7 domes; three players, 10 domes; four players, 13 domes.
You play in the order shown on the player-order track. This usually means you are not playing in clockwise order.
If you claim an action card and you already have 4 action cards, then you must discard one of the old ones. If you discard an available action card in this situation, you may use its action immediately.
When you build a structure or city, you can use biomatter as a replacement for kelp and steelplast.
Special cards do not have a discard pile. One-or two-credit Special cards return to the bottom of the deck if they are discarded. Discarded three-credit Special cards simply leave the game.
When you pay to play a Special card with an instant effect, it does not return to its deck. Instead, you keep it under your player board.
During Production, tunnels produce only if they are adjacent to a city.

VARIANTS

>> 1) GOVERNMENT CONTRACTS

Place 3 random government contracts on the spaces of the main board at the beginning of the game.

During play, any player may claim a government contract as soon as he or she meets all its criteria.

Use these cards to give your game intermediate goals that players can compete for. Shuffle the deck of contract cards and draw 3 at random. Place them on the spaces of the main board at the beginning of the game. Return the remaining cards to the box.

During play, any player may claim a government contract as soon as he or she meets all its criteria. The player keeps the card and immediately gains its benefits. Claimed contracts are not replaced.

>> 2) THE OTHER SIDE OF THE PLAYER BOARDS

If you decide to try this other side, everyone in the game should use it.

Some sites may have surcharges for building on them.

As additional kind of bonus there are now production multipliers; a 2x multiplier indicates, that the usual amount is produced one extra time.

The other side of the player boards is for experienced players. The cities have variable numbers of building sites. The black-and-red sites are places where you must pay surcharges - extra resources to build. They can give you immediate bonuses or increased production. If you decide to try this other side, everyone in the game should use it.

>> SURCHARGES

Some sites may have surcharges for building on them (these are not on the side of the player board recommended for your first game). A surcharge is applied after any discounts or cost reductions you may have. For example, if an effect allows you to build on a site for free, you still must pay the surcharge if you choose a site that has one.

The surcharge applies only to building on the site – it does not also apply to upgrading.

>> PRODUCTION MULTIPLIERS

Production multipliers indicate that the usual level of production is produced multiple times. More specifically, the two-times multiplier shown on the side means that the structure produces the usual amount one extra time. For example, two upgraded desalination plants at a connected city will normally produce 3 credits and 2 biomatter. If one of them has this multiplier, it will produce an additional 1 credit and 1 biomatter, for a total of 4 credits and 3 biomatter.

As you can see from the example, the multiplier applies to the usual production of an upgrade, but not to any additional production associated with the site.

Multipliers are not applicable outside the Production phase. For example, if a Trial Run allows you to gain the production from an upgraded desalination plant with this multiplier, you gain only 1 credit and 1 biomatter. But during Production, it will produce 2 credits and 2 biomatter.

When you build a city on this site, you must pay a surcharge of 3 steelplast and 3 credits. A connected symbiotic city on this site produces 6 points during Production (instead of 2). A nonsymbiotic city does not produce points by itself and yields no bonus on this site. The production bonus does not apply to any buildings or tunnels.

When you build a tunnel on this site, you must pay a surcharge of 1 credit. A tunnel on this site produces three times during Production if it is adjacent to a connected city. This means that a non-upgraded tunnel would produce 3 credits and an upgraded tunnel would produce 3 credits and 3 points.

This production bonus applies only if you have built both tunnels. And, as usual, it applies only if the tunnels are adjacent to a connected city. In that case, you gain an extra 2 credits when the tunnels produce during Production. This extra production does not depend on whether the tunnels are upgraded.

When you build a tunnel on this site, you must pay a surcharge of 1 credit and 1 steelplast. During Production, the connected metropolis produces an additional 2 points. This bonus does not depend on the tunnel‘s production.

When you build a city on this site, you must pay a surcharge of 2 science and 2 credits. You immediately gain 6 points, whether the city is connected or not.

>> 3) SOLO GAME

Use the advanced side of a player board and the two-player side of the main board.
Take three tiles in a non-player color and use them to occupy the rightmost action slot of each color.
At the end of each round, you take back your action tiles and move all non-player action tiles one space clockwise.
If you did not advance on the Federation track, play your next round with a fourth randomly chosen occupied slot.
You win if you finish with at least 7 connected cities and at least 100 points.

To play Underwater Cities by yourself, use the advanced side of a player board and the two-player side of the main board. The number of symbiotic domes is not limited in this variant. Set up the game as you would for two players, except do not use this metropolis tile (shown here).

Take three tiles in a non-player color and use them to occupy the rightmost action slot (first slot, if you move around clockwise) of each color. Next time you can occupy second, third etc. action slot of each color. You are going “first”, so your marker should start below space 4 of the Federation track. You will not need your player-order track marker.

>> GAMEPLAY

Play your round as usual. At the end of each round, you take back your action tiles and move all non-player action tiles one space clockwise.

If you did not advance on the Federation track, play your next round with a fourth occupied slot determined by this way:

Flip over the top card of the current era’s deck. Add its digits together to get a number.
Starting with the first green action slot (as “1”) count around clockwise until you get to that number. Place the new action tile on that slot, if it is empty, otherwise, move the action tile clockwise to the first empty slot.

The 3 non-player tiles of the same color always move one space clockwise. The fourth tile is always placed randomly, and only if you did not advance on the Federation track during the round.

>> GOAL

You win if you finish with at least 7 connected cities and at least 100 points. Track your score and try to beat your previous best.

Note: It is not possible to play the solo game with the government contracts.

NOTES ON CARD EFFECTS

Your cards affect your own board during your own turn. Your production cards apply only to your own production. There is nothing that can affect another player’s board. None of your cards’ effects apply during another player’s turn.

ANY AVAILABLE SLOT: This includes the always-available slot.
ANY SLOT OCCUPIED BY ANOTHER PLAYER: This is any occupied slot, except those occupied by your action tiles. This does not include the always-available slot, because it is never considered to be occupied. In a four-player game, a slot occupied by you and another player does not count as a slot occupied by another player (because it is occupied by you).
AT THE END OF THE GAME, GAIN 1 POINT FOR EVERY 3 CONNECTED FARMS YOU HAVE: As above, count up all your connected farms, divide by three, and round down. That´s how many points you gain.
BUILD: Anything you build must be built on a legal site.
BUILDING: A building is a farm, desalination plant, or laboratory. Tunnels and cities are not buildings.
CITY: If it is not otherwise specified, this refers to nonsymbiotic cities and symbiotic cities.
CONNECTED: This always means “connected to your network”. For example, “If you have at least 3 connected desalination plants ...” means that the effect will trigger only if the desalination plants are in your network. Your network is explained here.
DISCOUNT: If it is not otherwise stated, the discount is subtracted from the usual cost. However, it is legal to apply several discounts and to combine them with a card that lets you pay a special cost. Discounts cannot take a cost below “free”. For example, if you have a discount of 2 credits on a tunnel that costs 1 credit and 1 steelplast, you treat it as a discount of 1 credit and simply pay 1 steelplast.
DURING PRODUCTION, 1 BIOMATTER PRODUCED: If you have nothing that produces biomatter during Production, this effect cannot be applied.
DURING PRODUCTION, YOU PRODUCE AN ADDITIONAL 1 KELP FOR EVERY 3 CONNECTED LABORATORIES: Count up the total number of laboratories connected to your network. Divide by three. Round down. That’s how much kelp you gain.
EXCHANGE: This is just like paying, except the effect can work either way. For example, you may pay 1 kelp to gain 1 steelplast or pay 1 steelplast to gain 1 kelp. You cannot exchange more than the specified amount. For example, a card that allows you to exchange 1 for 1 does not allow you to exchange 2 for 2.
EXPANSION SITE: Each city has a special building site that can only be built on if you play a Survey card. Expansion sites follow the usual rules – the chosen expansion site must be adjacent to a city or to a city site on which it is legal to build.
FARM, DESALINATION PLANT, LABORATORY, TUNNEL: Upgraded structures still count as structures. For example, an upgraded farm counts as a farm.
FOR FREE: If a cost is free, the card will say so. Once a cost is free, discounts have no further effect.
GAIN THE PRODUCTION FROM 1 UPGRADED STRUCTURE ADJACENT TO A CONNECTED CITY: Pick one upgraded structure at a connected city. On your player info card, look up what one of those, by itself, produces. Gain those resources. This does not impact on its production during the Production phase.
IF YOU ARE ON THE THIRD SPACE OF THE FEDERATION TRACK: This applies if your marker is on the space with the 3. This does not apply if your marker is on any other space.
MAY: A card’s effect is always optional. On certain cards, such as those that require payment for an instant effect, we use the word “may” to remind you of this rule, but the effect is optional even when the word is not used.
ONCE PER TURN: This always refers to your turn. There are no cards that refer to other players’ turns or other players’ boards.
PAY: Many cards allow you to pay a cost to get a benefit. As you would expect, if you can’t pay the cost, you do not get the benefit (however, you may play the card with no effect). If not otherwise specified, you pay the cost and gain the benefit only once. Cards that allow you to pay more to gain more will say so.
PERFORM THE ACTION IN A SLOT: This allows you to perform a second action. You do not play an action tile on this second slot and you do not play a second card.
SPECIFIED COST: Some cards specify how much you pay to build a structure or city. In this case, you do not pay the usual cost; you pay the specified cost instead.
STRUCTURE: A structure is a farm, desalination plant, laboratory, or tunnel. Cities are not structures.
USUAL COST: The usual cost is the cost printed on your player info card. It is the cost you usually pay to build the structure or build the city.
WHENEVER AN ACTION SLOT GIVES YOU AT LEAST 1 STEELPLAST, GAIN 1 POINT: If the slot allows you to choose between gaining steelplast and doing something else, you gain the point only if you choose to gain the steelplast. The effect is not triggered by steelplast gained from other sources. For example, the action slot that allows you to advance 2 spaces on the Federation track cannot trigger this effect, not even if the advancement gives you 1 steelplast.
WHENEVER YOU BUILD A CONNECTED CITY’S SECOND LABORATORY: If it is not connected, the effect will not trigger. A third laboratory will not trigger this effect.
WHENEVER YOU BUILD THE SECOND TUNNEL ON THE SAME TURN: This triggers on any turn on which you build at least two tunnels. It triggers immediately after you build the second tunnel, even if you are still in the middle of resolving an effect.
WHENEVER YOU COMPLETE A CONNECTED CITY’S SECOND UPGRADED FARM: The city must be connected. It must have at least two farms, but it may have more. It must already have exactly one upgraded farm. As soon as you upgrade a second farm, the effect triggers immediately.
WHENEVER YOU USE THE DEPICTED ACTION SLOT: This effect triggers when you choose the slot as your action for the turn or when you are using the slot as the result of a card effect. The triggered effect modifies the rules of the action slot for the duration of your turn.
YOU MAY UPGRADE 1 OR 2 FARMS: For each, pay 1 credit or 1 science. To upgrade 2 farms, you could pay 2 credits, 2 science, or 1 credit and 1 science.

Appendix

>> Action Slots

Build 2 desalination plants. (1-4 players)

Build 1 city. (1-2 players)

Advance 2 spaces on the Federation track. (1-4 players)

Gain 2 cards. Upgrade 1 structure by paying 1 science or gain 1 kelp. (1-2 players)

Either build 1 city; or gain 1 kelp. (3-4 players)

Either build 1 tunnel; or advance 1 space on the Federation track and gain 2 cards and 1 credit. (3-4 players)

Use one of your action cards. Gain 1 steelplast. (1-2 players)

Draw 1 Special card. (1-2 players)

Gain 2 steelplast and 1 kelp. (1-4 players)

Build 1 tunnel. Use one of your action cards. (1-2 players)

Build 2 farms; or build 2 laboratories (you cannot build 1 farm and 1 laboratory). (1-2 players)

Build 2 laboratories. (3-4 players)

Build 1 tunnel and 1 city. (3-4 players)

Build 2 farms. (3-4 players)

Use 1 of your action cards. Pay the usual cost to build a structure. Pay 1 science to upgrade the structure you just built. (3-4 players)

Build 1 city and 1 building. (1-4 players)

Gain 2 science; or upgrade 1, 2, or 3 structures, paying 1 science for each upgrade. The structures do not all have to be the same type. (1-4 players)

Build 2 tunnels. (1-4 players)

Use one of your action cards. Gain either 2 resources (they can´t be of the same type). (1-2 players)

Use 1 of your action cards. Draw 1 Special card. (3-4 players)

Gain 1 science, 1 steelplast, and 1 kelp. (3-4 players)

Discard your chosen card and gain 2 cards and 2 credits. This slot is always available, even if another player has used it already. (1-4 players)

>> Metropolises

At the end of the game, score 2 points for each Special card you played and paid for. This includes not only your claimed Special cards, but also those with instant effects. This does not include any Special action cards that you discarded.

At the end of the game, score points based on the number of connected cities you have: 4 points for five cities, 8 points for six cities, or 12 points for seven or more.

At the end of the game, score points for tunnels connected to the network: 5 points for eight tunnels, 7 points for nine, or 9 points for ten or more (don‘t forget that upgraded tunnels also count as tunnels).

At the end of the game, score 3 points for each metropolis connected to your network (this includes the brown and blue metropolises you started with, as well as any metropolis tile you may have gained during play).

At the end of the game, score 4 points for each set of 4 different upgraded structures. Count only buildings that are connected and tunnels that are adjacent to a city. In other words, you count whatever you have least – upgraded tunnels adjacent to a city, connected upgraded farms, connected upgraded laboratories, or connected upgraded desalination plants – and multiply that by four.

Instant effect: If you connect to this metropolis, immediately gain 2 points and 3 steelplast.

Instant effect: If you connect to this metropolis, immediately gain 4 credits and 1 point.

Instant effect: If you connect to this metropolis, immediately advance 3 spaces on the Federation track and gain 1 credit.

Instant effect: If you connect to this metropolis, immediately gain 1 kelp.

Production effect: If this metropolis is connected, gain 2 points during each Production phase.

Instant effect: If you connect to this metropolis, immediately advance 1 space on the Federation track and gain 3 kelp and draw one card.

Instant effect: If you connect to this metropolis, immediately gain 2 biomatter.

Instant effect: If you connect to this metropolis, immediately gain 1 steelplast and 1 science.

Production effect: If this metropolis is connected, gain 1 point during each Production phase.

Instant effect: If you connect to this metropolis, immediately gain 1 steelplast and 1 credit and draw 2 cards.

Production effect: If this metropolis is connected, gain 1 point during each Production phase.

Instant effect: If you connect to this metropolis, immediately advance 1 space on the Federation track.

Production effect: If this metropolis is connected, gain 2 points during each Production phase.

Instant effect: If you connect to this metropolis, immediately advance 1 space on the Federation track and gain 2 credits, 1 kelp and 1 steelplast, and draw one card.

Instant effect: If you connect to this metropolis, immediately gain 1 steelplast and draw one card.

Production effect: If this metropolis is connected, gain 2 points during each Production phase.

Hints for handling

Player View

The player view consists of several parts.

In the middle there is a border in the player's color which encloses the player's player board. The lower left corner of this area shows 4 different symbols:
If you click on one of these symbols, it allows you to change the view from the player board () to the played cards of the player (), to the overview card () or to the scoring card ().

Below this border there is another border in the player's color which encloses the hand cards of the player. If during the player's turn a new hand card is drawn, it will first only show the back of the card in order to allow the player to still undo their turn if needed.

On the right side there are the player infos of each player. A click in the player info of a player switches to the player view of that player (thus allowing you to see the player board and played cards of that other player).

Player info

In the upper left corner of the player info you can see how many action tiles the player has left. Below that you can see the resources, from left to right: (Kelp), (Steelplast), (Science), (Biomatter) and (Credits). The number below the resources indicates how many units of the resource the player owns. The number in the upper right corner of each resource shows how many units of this resource the player will produce during the next production phase. The red number in the upper left corner of the Kelp resource shows how much Kelp the player has to pay at the end of the production phase for feeding their connected cities.

After the resources it shows the current score, considering everything that is already certain. This includes points that are usually scored at the end of the game in case they are provided without exchanging resources for points. The display tab with the scoring card shows these game end points which are already included in the current score.

Like for resources, the upper right corner of the points symbol shows how many points the player will score during the next production phase.

Player board

This view shows the player board of the player. Each metropolis, city or building which is not yet connected to the network is marked with a red cross. The tunnels which are not adjacent to a city and thus do not produce are marked likewise.

The question mark icons on the player board can be clicked to get additional information about bonus payouts, extra costs or extra production which apply in this area of the player board.

If you move your mouse over a connected city, it will show you how many points the player will score for this city at game end (this is already included in the current score during the game, see player info).

If you move your mouse over a metropolis, a magnified version of the metropolis tile will be shown in the middle of the player board.

Played cards

In this view the player's played cards are shown, grouped by the type of the card. The action cards are to the left, next the production cards, then the permanent cards, then the end scoring cards, finally the special cards with a one-time immediate effect.

The cards are shown with some overlap in order to save space. To see the complete cards together with a help text, you can click on the magnifying glass icon.

Overview card

In this view the overview card with the costs and production values of the different structures and cities is shown.

The left column shows the structure or city for which the other columns contain their cost/production values (from top to bottom: farm, desalination plant, laboratory, tunnel, city and symbiotic city).

The second column shows the building costs of the structure or city, respectively. Note that the building costs can differ from these standard costs due to card effects.

The following columns show the income during the production phase, first for single structures / cities, then for upgraded structures, then for a pair of upgraded structures in the same city.

The resources gained during the production phase are shown with a multiplier (e.g. 2x) which indicates how often the player receives this income due to the connected structures he owns.

Scoring card

In this view the scoring card itself is shown in the upper left corner. It serves as a memory aid and explains symbolically how the end scoring works. Please also read the corresponding section in the rules.

Next to it the points for the brown metropolis and the points from connected cities are shown. As long as the brown metropolis is not connected to the network, it scores 0 points.

The points from end scoring cards played by the player follow below. In case it is an end scoring card which allows to convert resources into points, a question mark is shown instead of a point value. The reason is that it may depend on production effects where the player has a choice how many points the end scoring card will provide. All other end scoring cards are already counted towards the current score of the player.

Action slots

On the left side the action slots are shown. In games with 3 or 4 players or when playing with the "Government Contracts" variant the action slots are partitioned into 3 columns, where each column shows the action slots of one color. When playing with 1-2 players (without "Government Contracts") there will be two columns with action slots, the first two rows contain the green action slots, then follow the red action slots, and finally the yellow action slots. If you prefer the view with 3 columns, you can choose this view also for 1-2 player games in the settings.

The used action slots show the action tile of the player who has used the slot, with a number on top to indicate whether it was the first, second or third action of the player. When playing with 4 players it can happen that an action slot is used twice. In this case the left half of the action slot will show the action tile of the one player, the right half of the action slot will show the action tile of the second player who used this slot.

For the solo game the relative position of the action slots is relevant; in the Yucata implementation the action slots of the same color are shown in the order in which they will be occupied by the action tiles of the neutral player color. In the standard view the upper left action slot of each color group would be occupied first, in the next round the action slot in the upper right. In the view with 3 columns the action slots of each color would be occupied from top to bottom.

Action stack

As soon as you have chosen an action slot and a hand card, the view changes from the action slots to a view that shows which actions you can still perform. Initially it shows your chosen action slot and the chosen hand card.

As mentioned in the rules, you have the choice whether you first activate the chosen action slot or the play the chosen hand card. If you have chosen a card which does not have the same color as the chosen action slot, it will be automatically discarded. Likewise if you have chosen a card with a matching color and it doesn't matter whether the card is played before or after activating the action slot, it will be automatically played.

In case you cannot or don't want to play the chosen hand card, you can click on the symbol with the trash icon below the card in order to discard the card.

When performing the chosen combination of hand card and action slot it can happen that you can choose between more than one action at once, and that performing one action triggers another action. This is displayed as a stack, where the lowest level shows the actions you can currently choose from. A continuous line is shown between the different levels. The action(s) which triggered the action choices on the lowest level is shown with a dashed border.

In order to simplify the display, all actions are shown which you can theoretically perform, even if choosing one will exclude others. As soon as you have chosen an action, all actions which will be excluded by this choice will be removed.

If you do not want to perform another action from the current level, you can click on the "Pass" button in the lower right. Note that you can only pass if you have already performed at least one action from the chosen action slot.

Drawing cards

In order to allow players to undo their turn, the cards which are drawn during the turn are initially only shown face down. Only after finishing your turn you will be able to see the cards which you have drawn. As an exception, if you draw special cards from the deck, they will be shown immediately, but you can only draw special cards in case you have already performed at least one action from the chosen action slot, or if after drawing the special card you can definitely still perform an action from the chosen action slot. The same exception holds for the card which allows you to draw two blue metropolis tiles.

Era track

The era track is leftmost. The era marker (beige) shows the current round, the number inside the marker indicates the sub-round (whether the 1st, 2nd or 3rd action token is being placed).

Settings

To open the settings you have to click on the symbol in the top right corner with the three lines. From the menu you can then choose the item "Settings". The settings allow you to choose some general options provided by the framework (not specific to Underwater Cities). The option "3-column layout" is specific to Underwater Cities and determines whether the action slots are shown in 3 columns or in 2 columns. This has further implications on where the special cards are displayed. Choosing the layout with 2 columns only applies to games with 1-2 players without the "Government Contracts" variant.

Moreover you have the option to pin the chosen view such that it is not automatically switched to the view of the player on turn. This makes it easier to plan your next turn during the turn of another player.

Optional Actions

Several cards have optional choices, for example cards which allow you to do something once per turn, or when triggering a certain condition. In general, once you have clicked a card, the logic will assume that you want to use it. So instead of clicking the card, click on the Pass button in the lower right corner if you don't want to use the card's effect.

Permanent cards that can be used once per turn will always need you to click the Pass button before you can finish the turn (unless the card cannot be used, anyway), so that you cannot accidentally forget to use them. If you actually want to use them, click on the card instead of the Pass button.

Government contracts

When playing with government contracts, most of them will be awarded automatically as soon as you fulfill the conditions of the contract.

For contracts which allow you to build a building for free, you have to click the contract card yourself when you want to claim it. The reason is that it may cost additional resources if you place a building on certain building locations, and you may not have these resources in the moment when you could first claim the government contract.