r1bq1b1r/3kp3/p5pp/2pnPpN1/2P2B2/N2P1P1P/PP6/R3KBR1 b Q - 0 21
FEN state: r1bq1b1r/3kp3/p5pp/2pnPpN1/2P2B2/N2P1P1P/PP6/R3KBR1 b Q - 0 21 ; Best move: d5f4
The current state of the chess board is: Black rook at a8, black bishop at c8, black queen at d8, black bishop at f8 and black rook at h8. Black king at d7 and black pawn at e7. Black pawn at a6, black pawn at g6 and black pawn at h6. Black pawn at c5, black knight at d5, white pawn at e5, black pawn at f5 and white knight at g5. White pawn at c4 and white bishop at f4. White knight at a3, white pawn at d3, white pawn at f3 and white pawn at h3. White pawn at a2 and white pawn at b2. White rook at a1, white king at e1, white bishop at f1 and white rook at g1. White queenside is the only castle move available. Half move number is 0. Full move number is 21. Black to move.