r1bq1b1r/p3kp2/3p1n2/Rpp1p1pp/1nP1P3/7P/3PQPPR/1NB1KBN1 w - - 0 21
FEN state: r1bq1b1r/p3kp2/3p1n2/Rpp1p1pp/1nP1P3/7P/3PQPPR/1NB1KBN1 w - - 0 21 ; Best move: a5b5
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 pawn at a7, black king at e7 and black pawn at f7. Black pawn at d6 and black knight at f6. White rook at a5, black pawn at b5, black pawn at c5, black pawn at e5, black pawn at g5 and black pawn at h5. Black knight at b4, white pawn at c4 and white pawn at e4. White pawn at h3. White pawn at d2, white queen at e2, white pawn at f2, white pawn at g2 and white rook at h2. White knight at b1, white bishop at c1, white king at e1, white bishop at f1 and white knight at g1. Both players have exhausted their castles. Half move number is 0. Full move number is 21. White to move.