1rb1k2r/1p1pqppp/1Bp5/p3p1P1/3P4/PPP1nN1P/5P2/1RQ1KB1R b k - 0 21
FEN state: 1rb1k2r/1p1pqppp/1Bp5/p3p1P1/3P4/PPP1nN1P/5P2/1RQ1KB1R b k - 0 21 ; Best move: e3d5
The current state of the chess board is: Black rook at b8, black bishop at c8, black king at e8 and black rook at h8. Black pawn at b7, black pawn at d7, black queen at e7, black pawn at f7, black pawn at g7 and black pawn at h7. White bishop at b6 and black pawn at c6. Black pawn at a5, black pawn at e5 and white pawn at g5. White pawn at d4. White pawn at a3, white pawn at b3, white pawn at c3, black knight at e3, white knight at f3 and white pawn at h3. White pawn at f2. White rook at b1, white queen at c1, white king at e1, white bishop at f1 and white rook at h1. Black kingside is the only castle move available. Half move number is 0. Full move number is 21. Black to move.