rn1k1b1r/1p4p1/PP1p1p2/2p1p2p/1NP3n1/4PP2/1B1PN2P/Rb1QK2R b KQ - 1 20
FEN state: rn1k1b1r/1p4p1/PP1p1p2/2p1p2p/1NP3n1/4PP2/1B1PN2P/Rb1QK2R b KQ - 1 20 ; Best move: c5b4
The current state of the chess board is: Black rook at a8, black knight at b8, black king at d8, black bishop at f8 and black rook at h8. Black pawn at b7 and black pawn at g7. White pawn at a6, white pawn at b6, black pawn at d6 and black pawn at f6. Black pawn at c5, black pawn at e5 and black pawn at h5. White knight at b4, white pawn at c4 and black knight at g4. White pawn at e3 and white pawn at f3. White bishop at b2, white pawn at d2, white knight at e2 and white pawn at h2. White rook at a1, black bishop at b1, white queen at d1, white king at e1 and white rook at h1. White kingside and white queenside castles are available. Half move number is 1. Full move number is 20. Black to move.