Summary

Players optionally build a map, then play a series of game rounds. The first player to reach 10 points wins. A setup option allows playing to 14 points instead.

Each game round consists of a Strategy Phase, Action Phase, Status Phase, and (possibly) Agenda Phase.

Fair Play

It is normal to have temporary alliances with other players in a game of Twilight Imperium 4th Edition. However, BGA terms of service forbid collusion with other users.

Unfair example: 2 players should not secretly collude to play a series of games where they only attack other players. This gives an unfair advantage to manipulate their rank.

Unfair example: 2 players should not secretly message each other to make deals when no one else at the table is aware of this.

Fair example: A group of friends might make a Friendly Mode table, and agree at the start that they can secretly talk to each other. This way all players are on equal footing.

Links

Twilight Imperium: 4th Edition is a very long, complex game. This rules summary provides a basic guide, but it is highly recommended to review the official Learn to Play guide.

* Learn to Play PDF

* Living Rules Reference PDF

* Images of all premade maps for BGA

* Unofficial rules reference website

Strategy Phase

In clockwise order, starting with the speaker, players take turns drafting strategy cards.

In 3-4 player games, each player will draft 2 strategy cards.

In 5-6 player games, each player will draft 1 strategy card.

If any cards are left, a trade good will be added to each one. When a player drafts a card with trade goods on it, they gain the trade goods.

Action Phase

In initiative order, players take turns performing actions. A player's initiative is equal to their lowest strategy card number. The lowest initiative player takes another turn after the highest initiative player takes their turn, and the Action Phase continues.

Each action is either a Strategic Action, a Tactical Action, or a Component Action. If a player has used all possible Strategic Actions, they may pass and will not perform any actions for the rest of the Action Phase. However, they can play reaction cards, use reaction effects, and perform secondary abilities of strategy cards as described below.

The Action Phase ends after all players have passed.

Systems and Planets

Each hexagon tile is a system, and each system may have 1 or more planets. Systems and planets can be clicked to examine their contents.

Players can gain control of planets, which give the player an exhausted planet card matching that planet. Once the planet card becomes non-exhausted later in the game, it can be exhausted again to spend resources or influence, printed on the card, to pay various costs.

Commodities and Trade Goods

Each player may gain Commodities by use of the TRADE strategy card. This is called "refreshing" Commodities, and refills the player up to the limit printed on their faction sheet.

Commodities are useless to the player themselves, but if they are given to another player, they become Trade Goods.

Trade Goods can be spent as resources or influence, except when casting votes, described later.

Command Tokens

Each player has a number of command tokens. Some of these are divided into tactic, fleet, and strategy categories. Some may be unused (called "reinforcements"), and some may be on the game board.

* Tactic command tokens are used to perform Tactical Actions, described later.

* Fleet command tokens determine how many ships a player may have in a given system.

* Strategy command tokens are used as a cost for certain effects.

* A command token in a system on the game board prevents the corresponding player from activating that system or moving / transporting units from it (except for the active system itself, described later).

Strategic Action

If the active player has a strategy card that is not exhausted, they may perform the primary ability of this card. To do this, they resolve each "PRIMARY ABILITY" bullet point effect at the top of the strategy card, in order from top to bottom.

After the primary ability finishes, each other player (even if they have passed) may perform the secondary ability of the same card. Players make this choice in clockwise order, starting with the player to the left of the active player. To perform the secondary ability, a player resolves each "SECONDARY ABILITY" bullet point effect at the bottom of the strategy card, in order from top to bottom.

Finally, the strategy card is exhausted and cannot be used again in the same Action Phase. Exhausted cards still count to determine player initiative.

Tactical Action

The Tactical Action is complex, so only a basic summary is given here. For more details on game concepts, please see the Learn to Play guide guide or the Living Rules Reference.

* Step 1. If the active player has at least 1 tactic command token, they may place it on a system which does not already contain one of their command tokens. This is called "activating" a system, and that system is called the "active system" during the Tactical Action.

* Step 2a. The active player may move one or more ships into the active system. Ships with a printed capacity value may be able to transport fighters and/or infantry. Ships may move from multiple locations, or even start and end their movement in the active system. However, all moving ships must finish their movement in the active system.

* Step 2b. Even if no ships were moved, a space cannon offense step occurs. This may allow player(s) to use SPACE CANNON abilities of certain units.

* Step 3. If two players now have ships in the active system, space combat occurs. The winner stays in the system, and the other player either loses their units or retreats their remaining units to an adjacent system, if possible.

* Step 4. If the active player is still in the active system, they may use BOMBARDMENT abilities and/or commit ground forces to invade 1 or more planets. If another player has units on those planets, ground combat(s) occur. If a player wins a combat against a defending player, or invades a planet they do not control, they gain control of it. They also gain the planet card, which is immediately exhausted.

* Step 5. If the active player has any units with PRODUCTION abilities (such as space docks) in the active system, they may pay resources to produce units. They do this by spending trade goods and/or exhausting planet cards that provide resources. The active player can produce even if they did not move any units. Produced units are placed in the active system.

Component Action

Some faction sheets, action cards, technology cards, and promissory notes have the text "ACTION:" at the top. The active player can use their turn to play such a card / perform such an effect, as long as they meet the condition of the card. For example, a technology card might require the player to exhaust it, or a faction ability might require a player to spend a strategy command token. Action cards are discarded after they are played.

Status Phase

The Status Phase has several steps which happen in order.

* Step 1. In initiative order, each player may score one public and/or one secret "STATUS PHASE" objective if they qualify for the condition / pay the cost. For example, if a card requires the player to spend 3 command tokens or pay 8 influence, the player must pay the cost at this time. Players gain victory points printed on the objective card when scoring it.

* Step 2. The next public objective is revealed. Stage II objectives give 2 points each, and are revealed after all Stage I objectives are visible. If it is impossible to reveal another objective at this point, the game ends early, and the player with the most victory points wins. If there is a tie, the tied player with the lowest initiative wins.

* Step 3. Each player draws 1 action card.

* Step 4. Each player removes all of their command tokens from the game board and places them in reinforcements.

* Step 5. Each player gains 2 new command tokens, and can redistribute all of their non-reinforcements command tokens between their tactic, fleet, and strategy pools.

* Step 6. Each player readies all of their exhausted cards, including strategy and planet cards.

* Step 7. Any damaged units are repaired.

* Step 8. All players return strategy cards to the common play area.

Agenda Phase or New Game Round

If the custodians token has been removed from Mecatol Rex, the Agenda Phase starts.

If the custodians token is still on Mecatol Rex, a new game round starts with the Strategy Phase.

Agenda Phase

In the Agenda Phase, 2 agendas are revealed, 1 at a time. After each agenda is revealed, players take turns casting votes. Turn order is clockwise, starting to the left of the speaker, and the speaker votes last.

To cast votes, players exhaust planets for influence. They are not allowed to spend trade goods at this time. For a specific agenda, each player only has one chance to cast votes. A player may exhaust several planets at once in order to spend a high number of influence, if desired.

A player cannot split their votes between multiple outcomes.

If a planet is being elected, players can only vote for controlled planets.

If a player does not wish to vote on an agenda, they may abstain.

After all players have voted or abstained, if a specific outcome has the most votes, that outcome resolves its effect. If more than one outcome is tied for the most votes, the speaker chooses one of the tied outcomes to resolve.

After the first agenda is resolved in the Agenda Phase, another agenda is revealed. Player votes and outcome resolution works the same way.

Ready Planets

All players ready any exhausted planets, in case they used them for voting.

New Game Round

Finally, a new game round starts with the Strategy Phase.

Table Host Custom Setup

This setup option is for advanced players who want to play a friendly mode game with complete control over the map and factions. The host can pick a premade map, or import a map string from a generator website.

For example, https://keeganw.github.io/ti4/ and https://milty.shenanigans.be/ can generate map strings.

IMPORTANT: If using a generator website, you will need to only select factions that are implemented on BGA, and disable POK (Prophecy of Kings) or otherwise custom content. Only base game factions, tiles, and hyperlanes are currently supported on BGA.