Setup
The Timeline is made up of ordered historical event cards spanning the 20th century.
The Timeline is a row of cards representing real historical events in chronological order. Each event space is either a Linchpin (a key event that, if changed, creates a Paradox and flips to a Ripplepoint) or a regular historical marker. The Timeline forms the central board of the game.
General
Linchpins are key timeline events; when altered they become Paradoxes and flip to Ripplepoints.
Each Linchpin card represents a pivotal historical event. When a player plays an Inverter card on a Linchpin, it is flipped to its Ripplepoint side, creating a Paradox at that location. The Ripplepoint shows an alternate-history outcome. Paradoxes must be repaired by playing the matching Patch card, which flips the Ripplepoint back to its Linchpin face.
Card play
Playing an Inverter on a Linchpin flips it to a Ripplepoint, creating a Paradox.
When an Inverter card is played targeting a Linchpin on the Timeline, that Linchpin is immediately flipped to its Ripplepoint side. This creates a Paradox at that spot on the Timeline. The presence of Paradoxes can cascade effects on nearby Ripplepoints and can block certain actions or trigger special card effects. The Paradox remains until a matching Patch card is played.
Card play
Playing a Patch card on a Ripplepoint removes the Paradox and restores the Linchpin.
Each Ripplepoint (Paradox) on the Timeline has a unique matching Patch card in the deck. When a player plays the correct Patch card on a Ripplepoint, it is flipped back to its Linchpin side, eliminating the Paradox. Patching paradoxes is sometimes required to fulfill a Mission or to enable other card plays.
Restriction
Players have a hand limit; holding 10 or more cards can be an alternate win condition.
Players may hold any number of cards in hand. However, if a player ever has 10 or more cards in their hand at the end of their turn, they immediately win the game (they have accumulated enough resources to return to their own time). Players draw back up to their starting hand size after each turn if they are below it.
Turn structure
On your turn, you must take exactly one action: play a card, use a special ability, or draw a card.
Each turn consists of exactly one primary action: (1) Play one card from your hand — an Action card, Patch card, or Artifact card — and resolve its effect. (2) Use your ID card's special ability if it grants a once-per-turn action. (3) Simply draw the top card of the deck and add it to your hand, forfeiting any other action. After your action, you draw back up to 3 cards if your hand is below 3. Play then passes clockwise.
Special
Each player has a secret ID card granting a unique special ability and defining a home timeline.
At the start of the game, each player receives a secret ID card representing their time traveler persona. The ID card specifies the player's home timeline (which configuration of the Timeline they need to restore or maintain to win) and grants a unique special ability usable during the game. ID cards are kept secret until the player wins or is forced to reveal.
Special
Each player holds a Mission card listing a specific set of artifacts or tasks needed to win.
In addition to their ID card, each player holds a Mission card that lists a specific combination of Artifact cards they must collect (or tasks they must complete) to win via their mission. Completing your Mission is one of the three ways to win the game. Mission cards are kept secret.