Thunder's Edge rules

Twilight Imperium: Thunder’s Edge is the second expansion for the Twilight Imperium: Fourth Edition base game. Its additional game systems take players through the Thunder’s Edge expedition, unlock powerful new abilities via faction-specific breakthroughs, and open the way into The Fracture, a hellish dimension overrun by Vuil’raith in the eons past. Additionally, six new factions join the galactic struggle, including the Council Keleres, previously only available with the Twilight Codices. This expansion also includes the Twilight’s Fall game mode, a wild and volatile way to play Twilight Imperium, where players take control of a Mahact King from the dark future and splice together a custom set of abilities as the game progresses.

Each card and sheet in this expansion has the Thunder’s Edge expansion icon to distinguish these components from the components in the Twilight Imperium: Fourth Edition base game and the Prophecy of Kings expansion. The expansion system tiles are numbered 92–128.

This expansion also includes all of the gameplay content from each Twilight Codex, previously only available in print-and-play format. Thunder’s Edge includes revised versions of these cards, each marked with the codex expansion icon to distinguish it from other components.

Using the diagram on the following page as a reference, perform the following steps to integrate Thunder’s Edge with the base game and Prophecy of Kings.

First, find the cards packaged with the “Codex Cards” cover card, also identifiable by the Twilight Codex expansion icon shown in the previous section.

If you do not have a previous version of the Twilight Codex, combine the following components with like components from the base game and expansions:

• 20 Action Cards
• 3 Relics
• 6 Exploration Cards
• 1 Keleres Faction sheet
• 1 Keleres Mech
• 5 Keleres Leaders
• 1 Keleres Promissory Note
• 2 Keleres Faction Technologies
• 1 “Custodia Vigilia” Planet Card
• 1 “Custodia Vigilia” Legendary Planet Ability

Then, for each remaining codex card, find and replace each corresponding component from the base game or Prophecy of Kings. In total, you will replace:

• 3 Faction Technologies
• 8 “Magen Defense Grid”
• 8 “X-89 Bacterial Weapon”
• 3 Secret Objectives
• 5 Promissory Notes
• 1 Mech
• 6 Leaders

If you do have a previous version of the Twilight Codex, simply replace all of its components with the updated versions included in Thunder’s Edge.

Additionally, Thunder’s Edge comes with its own complete sets of Alliance and Faction Reference cards. The print-and-play versions introduced by the Twilight Codex are not used.

Replace the “Construction” and “Warfare” strategy cards with the revised versions included with Thunder’s Edge.

Replace the “Mecatol Rex” system tile from the base game with the “Mecatol Rex” system tile that has a legendary planet icon.

If you are playing with the Prophecy of Kings expansion, replace the Jol-Nar’s “Ta Zern” leader with their “Agnlan Oln” leader.

If you are not playing with the Prophecy of Kings expansion, remove all Leaders, Mechs, and Exploration Cards, as well as the “Cultural Exchange Program” galactic event.

Finally, combine any remaining new cards with their respective decks, and shuffle the red-backed and blue-backed system tiles into their respective piles.

Components used in the Twilight’s Fall game mode are not used when playing a normal game. See the Twilight’s Fall component list in the Twilight’s Fall rulebook for a list of these components.

To set up a game of Twilight Imperium with the Thunder’s Edge expansion, follow the Complete Setup rules found in the rules reference with the following additions:

• STEP 1—DETERMINE SPEAKER: After the speaker has been determined, the players may, as a group, optionally choose or draw at random a galactic event card to put into play. Some galactic events may further modify setup. Advanced player groups are free to play with more than one galactic event, should they desire.
• STEP 3—GATHER FACTION COMPONENTS: In addition to their faction components from the base game and other expansions, each player takes their faction’s breakthrough card. The factions listed below take additional components:
• The Embers of Muaat: 1 Avernus Token
• The Nekro Virus: 7 Assimilator Z Tokens, 3 Helios Tokens, and 3 Helios Cards
• The Empyrean: 2 Void Tether Tokens
• The Crimson Rebellion: 1 Sever and 7 Breach Tokens
• The Deepwrought Scholarate: 5 Ocean Cards
• The Firmament: 5 Plot Cards, all Obsidian Components
• Last Bastion: 8 Galvanize Tokens, 3 Helios Tokens, and 3 Helios Cards
• STEP 4—CHOOSE COLOR: Players that wish to use the color-based command tokens and control tokens from the Twilight’s Fall game mode may choose to do so rather than the standard faction-specific command tokens and control tokens. This may help with board clarity for novice players.
• STEP 6—CREATE GAME BOARD: After the galaxy has been created, set aside the three tiles that make up The Fracture; these tiles may come into play during the game.
• STEP 7—PLACE GAME BOARD TOKENS: Place the Thunder’s Edge token, expedition side faceup, in the common play area.
• STEP 8—SHUFFLE COMMON DECKS: Shuffle the relic deck and place it in the common play area.

When playing at certain player counts or with the “Minor Factions” galactic event, the “Create Game Board” step (step 6) of setup is modified as described below.

This section describes the components and mechanics introduced in this expansion.

Players may venture to Thunder’s Edge to unlock powerful new abilities and potentially earn the right to claim the planet of Thunder’s Edge for their faction. Thunder’s Edge begins the game in play, off the board, with its expedition side—the side divided into six “slices”— faceup.

At the end of a player’s turn, they may commit to the expedition. To do so, they choose an unclaimed slice of the expedition and pay the indicated cost, placing one of their control tokens in that slice to indicate that it has been claimed.

The expedition costs are as follows:

• Spend 5 Resources
• Discard 2 Action Cards
• Spend 5 Influence
• Discard 1 Unscored Secret Objective
• Exhaust 1 Technology Specialty Planet
• Spend 3 Trade Goods

Once claimed, that slice cannot be claimed by another player, which means other players must choose a different cost to pay in order to contribute to the expedition. The first time a player claims one of the expedition slices, they gain their faction’s breakthrough. A player can claim multiple expedition slices in a game, but must choose a different unclaimed slice each time they do so.

When all slices are claimed, the expedition is complete; the player who claimed the final slice flips Thunder’s Edge to its planet side and places it in a system of their choice that does not contain a planet, a supernova, or a printed wormhole. Then, the player with the most control tokens on the expedition places that many infantry on Thunder’s Edge. In the case of a tie, the player who claimed the final slice chooses which tied player places infantry on Thunder’s Edge. Thunder’s Edge cannot be placed in The Fracture.

A breakthrough is a new type of faction-specific component, most commonly gained by interacting with Thunder’s Edge. A breakthrough will give each faction a unique new ability and grants synergy between two technology colors.

Synergy links two colors of technology. A technology or technology specialty of a color that a player has synergy with can count as the other color instead, for the purposes of researching technology and for scoring technology-related objectives. Even so, a technology can only count as one or the other at any given time, not both.

Each time a breakthrough is gained, there is a possibility that the fracture will come into play. When a player gains their breakthrough, regardless of the source, if The Fracture is not already in play, they roll one die. If their die roll is equal to 1 or 10, they put The Fracture into play.

The Fracture is an enigmatic area of space that is not connected to the rest of the galaxy. When The Fracture comes into play, the player that brought it into play places it along any edge of the game board, based on player count, as shown in “The Fracture” diagram. They then place neutral units as indicated on the back of The Fracture’s tiles.

If The Fracture was brought into play by a breakthrough roll, the rolling player places ingress tokens on the game board. For each synergy color on their breakthrough, that player must choose three systems that contain matching technology specialties, if able, and place ingress tokens in those systems. A system cannot have more than one ingress token, and no more than six ingress tokens can be placed in this way.

If The Fracture was brought into play by another ability, or by a breakthrough that does not have synergy (as is the case with the Nekro Virus faction), the player chooses four planets and places an ingress token in those planets’ systems. Each planet must be in a different system and must have a different technology specialty. If there are not four different technology specialties in play, the remaining ingress tokens are not placed.

Finally, the players place an ingress token in the Thunder’s Edge system, if it is in play, or in the Mecatol Rex system, if the expedition has not been completed.

Regardless of where The Fracture is placed, its systems are not adjacent to the systems it is touching, and each of its systems is considered to be on the edge of the game board. Access to The Fracture is possible through ingress tokens. A system that contains an ingress is adjacent to each system in The Fracture that contains an egress. However, ingress systems are not adjacent to other ingress systems, and egress systems are not adjacent to other egress systems.

Planets inside The Fracture are highly rewarding. Each planet in the fracture has a relic icon. One planet, Styx, has both a relic icon and is a legendary planet.

When a player gains a planet card from the planet deck that has a relic icon, or when a game effect tells them to draw a relic, they draw the top card of the relic deck and place it faceup in their play area. Relics provide players with powerful abilities that can change the course of the game.

Many of the planets in this expansion are legendary planets, which are indicated by the legendary icon.

When a player takes control of a legendary planet, they also place its legendary planet ability card in their play area. Each legendary planet ability card grants its owner a unique and powerful ability. If a player gains control of an exhausted legendary planet ability card, it remains exhausted.

Neutral units are non-player forces that engage a player in combat if the player moves units to the planet or space area that those neutral units occupy. Neutral units’ combat stats are indicated on the neutral unit reference card, and their rolls are made by any player other than the active player. During combat, hits are assigned to neutral units in the order presented on the neutral unit reference, prioritizing units lower on the reference card first (for example, hits will always be assigned to neutral destroyers before they are assigned to neutral cruisers).

Neutral units always use unit abilities when they can (sustain damage, space cannon, etc.) but are otherwise unable to use any other abilities. Neutral units do not take turns or perform any other game function unless explicitly stated by rule or ability text.

Neutral units count as other player’s units for the purpose of resolving players’ abilities and other game effects. There is, however, no “neutral player,” and neutral units are incapable of making decisions; in the unlikely event that a decision needs to be made for a neutral unit, the speaker makes that decision instead.

If an ability instructs a player to purge a component, that component is removed from the game and returned to the box.

Some systems contain space stations. A player gains control of a space station from the deck or from another player when they are the only player that has ships in its system. They do not lose control of the station if those ships move out of its system. Each space station has a corresponding planet card, which is gained exhausted and is spent, readied as if it were a planet. However, structures and ground forces cannot be placed on or committed to space stations, and they do not count as planets for the purpose voting, objectives, or controlling a home system.

A player’s commodity value is increased by 1 for each space station they control; corresponding commerce tokens are placed in their commodity pool as a reminder. A player that controls a space station can resolve transactions with other players that control a space station, even if they are not neighbors. Finally, players can exhaust a space station at any time to convert their commodities to trade goods.

An entropic scar is a new kind of anomaly. All unit abilities (Sustain Damage, Production, Planetary Shield, Space Cannon, Bombardment, Deploy, and Anti-Fighter Barrage) cannot be used by or against units inside of an entropic scar. Text abilities are unaffected. Additionally, wormholes that would be placed inside of an entropic scar are discarded instead.

At the start of the status phase, a player that has ships in an entropic scar can spend a token from their strategy pool to gain one of their faction-specific technologies.

Planets that have dual planet traits count as having both traits. When exploring one of these planets with the Prophecy of Kings expansion, the exploring player can choose to draw a card matching either of the planet’s traits (but not both).

Some planets have two technology specialties. These planets can be exhausted when researching technology to satisfy either or both prerequisites simultaneously.

Some game effects allow a player’s units to coexist with other units on a planet. When a unit or units coexist with another player’s units, they do not trigger combat. The player whose units triggered coexistence does not gain or retain control of the planet; if they already controlled it, the player they are now coexisting with gains control of it instead, exhausted. Coexisting structures are always blockaded. If the coexisting player places, produces, or moves additional units onto that planet, those units also coexist. If a player’s coexisting units become the only units on a planet, that player gains control of the planet.

Coexisting units can be bombarded. When a player makes a bombardment roll against a planet, they choose which of their units with bombardment are bombarding which other player’s units, rolling against each player separately.

Coexisting units can have combat initiated against them by units being committed to the planet that contains them, including units that they were already coexisting with. The activating player may choose not to engage the coexisting units, however, and leave the coexisting units in a state of coexistence. If a player does wish to engage coexisting units, they may optionally engage a coexisting player’s units after winning a combat against the planet’s owner, initiating separate combats against any coexisting player as desired.

Likewise, a coexisting player may choose to end their coexistence by activating the coexisting unit’s system and committing the coexisting units against the planet they are coexisting on. If they win the ground combat, they cease coexisting and gain control of the planet as normal.

When scoring objectives, a coexisting player counts as controlling the planet they are coexisting on; they do not count as controlling the planet for any other game ability or effect.

When playing with five players, or when playing with four players and the Prophecy of Kings expansion, the galaxy is set up with hyperlane tiles (see “Game Board Setup” on page 7). Each contiguous line created by one or more hyperlane tiles is a hyperlane. System tiles connected by a hyperlane are considered adjacent for all purposes.

Hyperlane tiles improve balance in the starting positions for each player, so players in five-player games do not receive extra trade goods for having a particular starting position.

Hyperlane tiles are not systems. They cannot have units on them and they cannot be targets for effects or abilities.

Galactic events are optionally selected during game setup and can change the parameters of play. Each event is different and contains the rules needed to play.

These cards contain a short summary of a faction’s capabilities, including those granted by cards in Prophecy of Kings. These cards are also used during setup of the Twilight’s Fall game mode and with Galactic Events to determine random factions.

These cards are a reference for when playing with the Prophecy of Kings “Alliance” promissory note. These cards are also used in the Alliance game variant, in some Galactic Events, and with the Yin Brotherhood’s breakthrough card.

When gained for any reason other than a reference to an “Alliance” promissory note, the gaining player places the card in their play area. They can use its ability.

This token is a player aid included to facilitate ease of play when resolving simple uses of the “Diplomacy” strategy card’s primary ability. It represents a command token from each player. It cannot be used to bring a player above the component limit for command tokens and should not be used when interacting with abilities that remove command tokens.

In this game variant, players form teams of two against up to three other alliances. This can be played with four, six, or eight players.

To accommodate team play, the rules are modified as follows:

The Twilight Imperium community is filled with many talented (and cheeky) map-makers! Check out one of the premade maps below or get involved with the Twilight Imperium community online to add a little spice to your galactic cartography.

This section includes clarifications about timings, interactions, and easily overlooked rules. If the players have a question, they should look here or consult the Living Rules Reference online.