r1b1kb1r/pp1pn1p1/5p2/2p1p1B1/1nP1P3/1PNP1PP1/q7/R3KBN1 b q - 1 21
FEN state: r1b1kb1r/pp1pn1p1/5p2/2p1p1B1/1nP1P3/1PNP1PP1/q7/R3KBN1 b q - 1 21 ; Best move: a2a1
The current state of the chess board is: Black rook at a8, black bishop at c8, black king at e8, black bishop at f8 and black rook at h8. Black pawn at a7, black pawn at b7, black pawn at d7, black knight at e7 and black pawn at g7. Black pawn at f6. Black pawn at c5, black pawn at e5 and white bishop at g5. Black knight at b4, white pawn at c4 and white pawn at e4. White pawn at b3, white knight at c3, white pawn at d3, white pawn at f3 and white pawn at g3. Black queen at a2. White rook at a1, white king at e1, white bishop at f1 and white knight at g1. Black queenside is the only castle move available. Half move number is 1. Full move number is 21. Black to move.