rnbq1b2/1p1p3p/5prk/p1p1pPp1/n3P1PP/P1NP1B2/RPP1KN2/2BQ2R1 b - - 4 21
FEN state: rnbq1b2/1p1p3p/5prk/p1p1pPp1/n3P1PP/P1NP1B2/RPP1KN2/2BQ2R1 b - - 4 21 ; Best move: a4c3
The current state of the chess board is: Black rook at a8, black knight at b8, black bishop at c8, black queen at d8 and black bishop at f8. Black pawn at b7, black pawn at d7 and black pawn at h7. Black pawn at f6, black rook at g6 and black king at h6. Black pawn at a5, black pawn at c5, black pawn at e5, white pawn at f5 and black pawn at g5. Black knight at a4, white pawn at e4, white pawn at g4 and white pawn at h4. White pawn at a3, white knight at c3, white pawn at d3 and white bishop at f3. White rook at a2, white pawn at b2, white pawn at c2, white king at e2 and white knight at f2. White bishop at c1, white queen at d1 and white rook at g1. Both players have exhausted their castles. Half move number is 4. Full move number is 21. Black to move.