1r4nr/2p1q1pp/1pn1b1k1/p2pppP1/PP3b2/5B1P/3PP3/BNRQK1NR b K - 3 21
FEN state: 1r4nr/2p1q1pp/1pn1b1k1/p2pppP1/PP3b2/5B1P/3PP3/BNRQK1NR b K - 3 21 ; Best move: c6b4
The current state of the chess board is: Black rook at b8, black knight at g8 and black rook at h8. Black pawn at c7, black queen at e7, black pawn at g7 and black pawn at h7. Black pawn at b6, black knight at c6, black bishop at e6 and black king at g6. Black pawn at a5, black pawn at d5, black pawn at e5, black pawn at f5 and white pawn at g5. White pawn at a4, white pawn at b4 and black bishop at f4. White bishop at f3 and white pawn at h3. White pawn at d2 and white pawn at e2. White bishop at a1, white knight at b1, white rook at c1, white queen at d1, white king at e1, white knight at g1 and white rook at h1. White kingside is the only castle move available. Half move number is 3. Full move number is 21. Black to move.