r3kb2/1bnpppr1/1q3npp/3P2P1/1p6/N1pQ3N/P1P1PP1P/4KB1R w K - 5 21
FEN state: r3kb2/1bnpppr1/1q3npp/3P2P1/1p6/N1pQ3N/P1P1PP1P/4KB1R w K - 5 21 ; Best move: a3c4
The current state of the chess board is: Black rook at a8, black king at e8 and black bishop at f8. Black bishop at b7, black knight at c7, black pawn at d7, black pawn at e7, black pawn at f7 and black rook at g7. Black queen at b6, black knight at f6, black pawn at g6 and black pawn at h6. White pawn at d5 and white pawn at g5. Black pawn at b4. White knight at a3, black pawn at c3, white queen at d3 and white knight at h3. White pawn at a2, white pawn at c2, white pawn at e2, white pawn at f2 and white pawn at h2. White king at e1, white bishop at f1 and white rook at h1. White kingside is the only castle move available. Half move number is 5. Full move number is 21. White to move.