r1b1kb2/pp1p1ppr/n1pn1q1p/4p3/1Q6/P3P1P1/1PPP1PRP/RNB1KBN1 w q - 5 13
FEN state: r1b1kb2/pp1p1ppr/n1pn1q1p/4p3/1Q6/P3P1P1/1PPP1PRP/RNB1KBN1 w q - 5 13 ; Best move: f1a6
The current state of the chess board is: Black rook at a8, black bishop at c8, black king at e8 and black bishop at f8. Black pawn at a7, black pawn at b7, black pawn at d7, black pawn at f7, black pawn at g7 and black rook at h7. Black knight at a6, black pawn at c6, black knight at d6, black queen at f6 and black pawn at h6. Black pawn at e5. White queen at b4. White pawn at a3, white pawn at e3 and white pawn at g3. White pawn at b2, white pawn at c2, white pawn at d2, white pawn at f2, white rook at g2 and white pawn at h2. White rook at a1, white knight at b1, white bishop at c1, white king at e1, white bishop at f1 and white knight at g1. Black queenside is the only castle move available. Half move number is 5. Full move number is 13. White to move.