4kb1r/r1q1pp2/p1b5/1pppn1Pp/P5n1/2PP3N/RPKQP1BP/2B4R w k - 0 21
FEN state: 4kb1r/r1q1pp2/p1b5/1pppn1Pp/P5n1/2PP3N/RPKQP1BP/2B4R w k - 0 21 ; Best move: c2b1
The current state of the chess board is: Black king at e8, black bishop at f8 and black rook at h8. Black rook at a7, black queen at c7, black pawn at e7 and black pawn at f7. Black pawn at a6 and black bishop at c6. Black pawn at b5, black pawn at c5, black pawn at d5, black knight at e5, white pawn at g5 and black pawn at h5. White pawn at a4 and black knight at g4. White pawn at c3, white pawn at d3 and white knight at h3. White rook at a2, white pawn at b2, white king at c2, white queen at d2, white pawn at e2, white bishop at g2 and white pawn at h2. White bishop at c1 and white rook at h1. Black kingside is the only castle move available. Half move number is 0. Full move number is 21. White to move.