r2q1br1/p1p3pp/n2k4/P2p1pN1/1pB1P2P/2P1K3/1P1P2P1/RNB4R b - - 3 21
FEN state: r2q1br1/p1p3pp/n2k4/P2p1pN1/1pB1P2P/2P1K3/1P1P2P1/RNB4R b - - 3 21 ; Best move: d5c4
The current state of the chess board is: Black rook at a8, black queen at d8, black bishop at f8 and black rook at g8. Black pawn at a7, black pawn at c7, black pawn at g7 and black pawn at h7. Black knight at a6 and black king at d6. White pawn at a5, black pawn at d5, black pawn at f5 and white knight at g5. Black pawn at b4, white bishop at c4, white pawn at e4 and white pawn at h4. White pawn at c3 and white king at e3. White pawn at b2, white pawn at d2 and white pawn at g2. White rook at a1, white knight at b1, white bishop at c1 and white rook at h1. Both players have exhausted their castles. Half move number is 3. Full move number is 21. Black to move.