Variants

python-chess supports several chess variants.

>>> import chess.variant
>>>
>>> board = chess.variant.GiveawayBoard()
>>> # General information about the variants
>>> type(board).uci_variant
'giveaway'
>>> type(board).starting_fen
'rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w - - 0 1'

See chess.Board.is_variant_end(), is_variant_win() is_variant_draw() is_variant_loss() for special variant end conditions and results.

Variant Board class UCI Syzygy
Standard chess.Board chess .rtbw, .rtbz
Suicide chess.variant.SuicideBoard suicide .stbw, .stbz
Giveaway chess.variant.GiveawayBoard giveaway .gtbw, .gtbz
Atomic chess.variant.AtomicBoard atomic .atbw, .atbz
King of the Hill chess.variant.KingOfTheHillBoard kingofthehill  
Racing Kings chess.variant.RacingKingsBoard racingkings  
Horde chess.variant.HordeBoard horde  
Three-check chess.variant.ThreeCheckBoard 3check  
Crazyhouse chess.variant.CrazyhouseBoard crazyhouse  
chess.variant.find_variant(name)

Looks for a variant board class by variant name.

Chess960

Chess960 is orthogonal to all other variants.

>>> chess.Board(chess960=True)
Board('rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1', chess960=True)

See chess.BaseBoard.set_chess960_pos(), chess960_pos(), and from_chess960_pos() for dealing with Chess960 starting positions.

UCI

Stockfish and other engines allow you to switch variants by setting the UCI_Variant option.

>>> import chess.uci
>>> import chess.variant
>>>
>>> engine = chess.uci.popen_engine("stockfish")
>>>
>>> board = chess.variant.RacingKingsBoard()
>>> engine.setoption({
...     "UCI_Variant": type(board).uci_variant,
...     "UCI_Chess960": board.chess960
... })
>>> engine.position(board)

Syzygy

Syzygy tablebases are available for suicide, giveaway and atomic chess.

>>> import chess.syzygy
>>> import chess.variant
>>>
>>> tables = chess.syzygy.open_tablebases("data/syzygy", VariantBoard=chess.variant.AtomicBoard)