rn2kbn1/4q2r/bp1p1p2/2pBpR2/pP3P2/P1P1P1N1/R1QP1KP1/1NB5 w q - 7 21
FEN state: rn2kbn1/4q2r/bp1p1p2/2pBpR2/pP3P2/P1P1P1N1/R1QP1KP1/1NB5 w q - 7 21 ; Best move: d5a8
The current state of the chess board is: Black rook at a8, black knight at b8, black king at e8, black bishop at f8 and black knight at g8. Black queen at e7 and black rook at h7. Black bishop at a6, black pawn at b6, black pawn at d6 and black pawn at f6. Black pawn at c5, white bishop at d5, black pawn at e5 and white rook at f5. Black pawn at a4, white pawn at b4 and white pawn at f4. White pawn at a3, white pawn at c3, white pawn at e3 and white knight at g3. White rook at a2, white queen at c2, white pawn at d2, white king at f2 and white pawn at g2. White knight at b1 and white bishop at c1. Black queenside is the only castle move available. Half move number is 7. Full move number is 21. White to move.