Where did I go wrong?
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9...Bxf3? loses a pawn to 10 Bxf7+ and 11 gxf3
11...Qh4? loses a tempo and a pawn 12 Bxf7+. Develop 11...Nge7.
14...Nxa5 is not as strong as 14...axb5 to save the knight, white can capture Rxa5.
16...Nc6? allows the passed pawn a6 to advance dangerously far with 17 axb7. Better 16...b5
20...Nxc6?? is the decisive mistake that fuels white's attack. You had to move your king either 20...Kd8 or 20...Kf8. Then Bc6 stands in the way of Qa4.
[Site "Chess.com iPhone"]
[Date "2024.03.07"]
[Round "?"]
[White "dlee426"]
[Black "HoosierLife"]
[Result "1-0"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[WhiteElo "861"]
[BlackElo "821"]
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.c3 d6 5.b4 Bb6 6.a4 a6 7.a5 Ba7 8.d3 Bg4 9.Qb3 Bxf3 10.gxf3 Qf6 11.Ke2 Qh4 12.b5 Qxf2+ 13.Kd1 Qxf3+ 14.Kc2 Nxa5 15.Qa4 Qxh1 16.bxa6+ Nc6 17.Bb5 Qxh2+ 18.Kb3 Ne7 19.axb7 Rb8 20.Bxc6+ Nxc6 21.Qxc6+ Ke7 22.Qxc7+ Ke6 23.Qc4+ Ke7 24.Qc7+ Ke6 25.Rxa7 Qh1 26.Kb2 Qg2+ 27.Ka1 Qc2 28.Ba3 Qxd3 29.Qc6 h5 30.Ra8 h4 31.Rxb8 Rxb8 32.Qc8+ Rxc8 33.bxc8=Q+ Kf6 34.Qf5+ Ke7 35.Qg5+ Kd7 36.Qxh4 f6 37.Qg4+ Ke7 38.Qxg7+ Ke8 39.Qxf6 Kd7 40.Qf5+ Ke7 41.Qg5+ Kd7 42.Qg7+ Ke6 43.Qg8+ Kd7 44.Qd5 Qxd5 45.exd5 e4 46.Bc1 Kc7 47.Be3 Kb7 48.Nd2 {1-0}