Developing the wrong knight first
1.e4 e5 2.f4 exf4 3.Nc3 Qh4+
- The mistake
- Answering the accepted gambit with 3.Nc3 rather than 3.Nf3.
- Why it costs
- 3…Qh4+ forces 4.Ke2 — the king walks, castling is gone, and the open f-file White gave a pawn for now points at his own king. There is no compensation for that.
- Instead
- 3.Nf3, which covers h4 and is played in ninety-nine games out of a hundred for exactly that reason. If you want the knight on c3, play it on move four.