Rules
The rules Kairos plays by: 5D Chess With Multiverse Time Travel, with the community tournament standard for stalemate (exiled kings).
New to 5D chess? The tutorial teaches it by playing, in short lessons.
The game
- Boards are up to 8×8. Pieces: king, queen, rook, bishop, knight, pawn, and the fairy pieces princess, unicorn, dragon, brawn, royal queen and common king.
- Castling and en passant work as in the original game. Pawns and brawns promote on the last rank, to a queen in the standard variants.
- Kings and royal queens are royal. A common king is not.
- Variants: every variant of the official game (Standard and its versions, Simple, Small, Very Small, Misc, Focused and Checkmate Practice) except Random and Global Warming.
Turns
- The present is the earliest latest-board among the active timelines. The side whose board it is moves.
- An action is one move on every playable board on the present, plus any moves on boards further on where it is also that side's turn. Then the side submits.
- An action is legal only if the mover's royal pieces cannot be captured afterwards.
Timelines
- Moving onto a board that is no longer the latest of its timeline creates a new timeline from that board.
- White's new timelines are numbered up from the main one, Black's down.
- A side may create at most one more active timeline than its opponent. Any timeline beyond that is inactive: it stays on the board and can be moved into, but it does not count for the present and never has to be played.
Check and mate
- Check: a royal piece can be captured next move, from the same board, another board or another time.
- Checkmate: in check, with no legal action.
- Softmate (
*in notation): in check, and every escape is a move into the past that creates a timeline. Not a result. - Stalemate: not in check, with no legal action. A draw, unless the exiled-kings rule applies.
Exiled kings
The community tournament rule:
At a stalemate, a side whose royal pieces all stand on inactive timelines loses.
- A side is exiled when it has royal pieces but none on an active timeline.
- If only one side is exiled, it loses the stalemate. If both or neither are, the game is drawn.
Endings
| Ending | Result |
|---|---|
| Checkmate | The checking side wins. |
| Stalemate, both or neither side exiled | Draw. |
| Stalemate, one side exiled | The exiled side loses. |
| Resignation | The opponent wins. |
| Time forfeit | The side that ran out of time loses. |
There is no repetition or fifty-move rule.