Skip to content

Ponderchess / Chess variants

Antichess

Chess in reverse: captures are compulsory, and the first player to lose all their pieces wins.
Created
19th century
Creator
Unknown
Where
Europe
Board
8×8
What changes
Lose everything to win
Also called
Losing chess, Giveaway, Suicide chess

Where it came from

Commonly attributed; details vary between sources

Versions of the “losing game”, in which the aim is to give your pieces away, were played in the 19th century. Rules varied, and the modern international rules, used online, were settled much later.

Compulsory captures make the game unusually forcing, which made it attractive to computer researchers. In 2016 the mathematician Mark Watkins published a computer proof that White wins by force after 1.e3.

Why it was made: A comic inversion of chess that turns out to be deeply calculable.

How it differs from chess

  • Captures are compulsoryIf you can capture, you must, though you may choose which capture to make.
  • No royal kingThe king is an ordinary piece. There is no check or checkmate, the king can be captured, and castling is not allowed. A pawn may promote to a king.
  • WinningYou win by losing all your pieces, or by having no legal move.
8
7
6
5
4
3
2
1a
b
c
d
e
f
g
h

Files a b c d e f g h
After 1.e3 b5, White must capture: Bxb5 is the only legal move.

Your first game

  • Think in forced sequences: a single capture can trigger a chain the opponent can’t avoid.
  • Lone pieces that can be forced to capture are liabilities; keep options for your opponent limited.

Notable moments

  1. 2016Mark Watkins publishes a computer proof that 1.e3 wins for White.

Questions

Is antichess solved?
Its opening is weakly solved: a 2016 computer proof shows 1.e3 wins for White with best play.
Can the king be captured in antichess?
Yes. The king is an ordinary piece with no special protection.

Sources