r1bqk1nb/p1p4r/1p1p1ppp/5P2/P1P1p1P1/1P1P2KP/3NQ3/R4BNR b q - 1 21
FEN state: r1bqk1nb/p1p4r/1p1p1ppp/5P2/P1P1p1P1/1P1P2KP/3NQ3/R4BNR b q - 1 21 ; Best move: g6f5
The current state of the chess board is: Black rook at a8, black bishop at c8, black queen at d8, black king at e8, black knight at g8 and black bishop at h8. Black pawn at a7, black pawn at c7 and black rook at h7. Black pawn at b6, black pawn at d6, black pawn at f6, black pawn at g6 and black pawn at h6. White pawn at f5. White pawn at a4, white pawn at c4, black pawn at e4 and white pawn at g4. White pawn at b3, white pawn at d3, white king at g3 and white pawn at h3. White knight at d2 and white queen at e2. White rook at a1, white bishop at f1, white knight at g1 and white rook at h1. Black queenside is the only castle move available. Half move number is 1. Full move number is 21. Black to move.