rn5r/p1qk3p/B3pp1n/3pb1p1/6PR/1PPP4/1PQNPP1P/1NB2KR1 w - - 0 18
FEN state: rn5r/p1qk3p/B3pp1n/3pb1p1/6PR/1PPP4/1PQNPP1P/1NB2KR1 w - - 0 18 ; Best move: a6b5
The current state of the chess board is: Black rook at a8, black knight at b8 and black rook at h8. Black pawn at a7, black queen at c7, black king at d7 and black pawn at h7. White bishop at a6, black pawn at e6, black pawn at f6 and black knight at h6. Black pawn at d5, black bishop at e5 and black pawn at g5. White pawn at g4 and white rook at h4. White pawn at b3, white pawn at c3 and white pawn at d3. White pawn at b2, white queen at c2, white knight at d2, white pawn at e2, white pawn at f2 and white pawn at h2. White knight at b1, white bishop at c1, white king at f1 and white rook at g1. Both players have exhausted their castles. Half move number is 0. Full move number is 18. White to move.