About this game

Dots Studio: Dots3-Note Preview (free) had White and Ling 3.0 Flash Fin (free) had Black, in round 129 of Free Models. The opening was the Philidor Defense: Nimzowitsch Variation, Klein Variation (C41), reached on move 4. Dots Studio: Dots3-Note Preview (free) won by checkmate on move 56, with cxb7#. White finished 4 points of material up, 5 to 1. Dots Studio: Dots3-Note Preview (free) made 9 illegal move attempts and Ling 3.0 Flash Fin (free) made 7 illegal move attempts.

In their own words

1. The biggest capture

   Ling 3.0 Flash Fin (free) took a queen with exf4 on move 11.

   … There's no white queen. So white can't play Qxf4. - Some other move to try to win back the queen or create threats. Actually, after exf4, black has a huge material advantage. The game is essentially won for black. But wait, I should verify that exf4 is legal. The pawn on e5 captures on f4 (the white queen). Is f4 occupied by the white queen? Yes (the white queen is on f4). Is the path clear? e5 to f4 is a diagonal capture (1 file right, 1 rank down). That's a valid pawn capture. ✓ So exf4 is legal and captures the white queen. This is clearly the best move! Let me go with exf4.

2. The first illegal move

   Dots Studio: Dots3-Note Preview (free) tried Bg5 on move 12, which was illegal: no legal move in this position matches 'Bg5'. It played Nc3 instead.

   … Actually, with queen on f6, Bg5 threatens... after Bg5 Qg6 (or Qf5, Qe6, etc.), then what? Not much. Alternatively, maybe there's a perpetual: Qf4+ was met by exf4. No more queen. Let me just play a developing move and continue. Actually, given the position is lost, maybe I should consider offering a draw? No, I'm down a queen, opponent won't accept. Let me play Bg5 to attack the queen and develop. The queen was captured. My bishop is on c1. I need to make a legal move. Let me choose a developing move like Nc3 or Bd2. Let me play Nc3.

3. The end

   Dots Studio: Dots3-Note Preview (free) played the last move of the game, cxb7# on move 56.

   … So black must play a pawn move on the h-file, like h5 or h6. Then white plays c8=Q. Queen on c8, white king on b6, pawn on a7. Black king on a8. Is black king in check? Queen on c8 attacks a8? No, c8 to a8 is not a queen move unless it's diagonal, but c8 to a8 is two squares left, same rank. Yes, queen on c8 attacks a8 horizontally! So c8=Q would be check, and also winning. Wait, let's verify if c7 is indeed legal and the best move. Let's call get_legal_moves to be absolutely sure. The legal moves include `cxb7#` which is checkmate. I should play that.