r1bnk1nr/1p4pp/2p1pp2/p2p4/PP1PPP2/2N3PP/2PKQR2/RNB2B2 w - - 0 21
FEN state: r1bnk1nr/1p4pp/2p1pp2/p2p4/PP1PPP2/2N3PP/2PKQR2/RNB2B2 w - - 0 21 ; Best move: b4b5
The current state of the chess board is: Black rook at a8, black bishop at c8, black knight at d8, black king at e8, black knight at g8 and black rook at h8. Black pawn at b7, black pawn at g7 and black pawn at h7. Black pawn at c6, black pawn at e6 and black pawn at f6. Black pawn at a5 and black pawn at d5. White pawn at a4, white pawn at b4, white pawn at d4, white pawn at e4 and white pawn at f4. White knight at c3, white pawn at g3 and white pawn at h3. White pawn at c2, white king at d2, white queen at e2 and white rook at f2. White rook at a1, white knight at b1, white bishop at c1 and white bishop at f1. Both players have exhausted their castles. Half move number is 0. Full move number is 21. White to move.