1rq1kb1r/ppp1ppB1/3pb2n/P5pp/1n1P1P2/RP2PNPP/2P1K1B1/2QN3R b k - 0 21
FEN state: 1rq1kb1r/ppp1ppB1/3pb2n/P5pp/1n1P1P2/RP2PNPP/2P1K1B1/2QN3R b k - 0 21 ; Best move: f8g7
The current state of the chess board is: Black rook at b8, black queen 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 c7, black pawn at e7, black pawn at f7 and white bishop at g7. Black pawn at d6, black bishop at e6 and black knight at h6. White pawn at a5, black pawn at g5 and black pawn at h5. Black knight at b4, white pawn at d4 and white pawn at f4. White rook at a3, white pawn at b3, white pawn at e3, white knight at f3, white pawn at g3 and white pawn at h3. White pawn at c2, white king at e2 and white bishop at g2. White queen at c1, white knight at d1 and white rook at h1. Black kingside is the only castle move available. Half move number is 0. Full move number is 21. Black to move.