r1b1kb2/5npr/p3p3/1pp2p2/1Nn1PPp1/PP1P2P1/5N1P/R1B2RK1 b - - 1 20
FEN state: r1b1kb2/5npr/p3p3/1pp2p2/1Nn1PPp1/PP1P2P1/5N1P/R1B2RK1 b - - 1 20 ; Best move: c4a5
The current state of the chess board is: Black rook at a8, black bishop at c8, black king at e8 and black bishop at f8. Black knight at f7, black pawn at g7 and black rook at h7. Black pawn at a6 and black pawn at e6. Black pawn at b5, black pawn at c5 and black pawn at f5. White knight at b4, black knight at c4, white pawn at e4, white pawn at f4 and black pawn at g4. White pawn at a3, white pawn at b3, white pawn at d3 and white pawn at g3. White knight at f2 and white pawn at h2. White rook at a1, white bishop at c1, white rook at f1 and white king at g1. Both players have exhausted their castles. Half move number is 1. Full move number is 20. Black to move.