r1bqk1nr/2pp4/p3p1p1/1p3Pbp/1n1P4/BPP1P3/PQ1KN1BP/RN5R w k - 2 20
FEN state: r1bqk1nr/2pp4/p3p1p1/1p3Pbp/1n1P4/BPP1P3/PQ1KN1BP/RN5R w k - 2 20 ; Best move: a3b4
The current state of the chess board is: Black rook at a8, black bishop at c8, black queen at d8, black king at e8, black knight at g8 and black rook at h8. Black pawn at c7 and black pawn at d7. Black pawn at a6, black pawn at e6 and black pawn at g6. Black pawn at b5, white pawn at f5, black bishop at g5 and black pawn at h5. Black knight at b4 and white pawn at d4. White bishop at a3, white pawn at b3, white pawn at c3 and white pawn at e3. White pawn at a2, white queen at b2, white king at d2, white knight at e2, white bishop at g2 and white pawn at h2. White rook at a1, white knight at b1 and white rook at h1. Black kingside is the only castle move available. Half move number is 2. Full move number is 20. White to move.