Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bc4/3...Nf6/4. Ng5/4...d5/5. exd5/5...Nxd5/6. Nxf7

=Fried Liver Attack= 6. Nxf7! is an aggressive Knight sacrifice with no sensible way to decline, Black's King becomes exposed while White gains momentum in development.

Theory table
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 * 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Nxd5