Chess Opening Theory/1. e4/1...e5/2. Qh5/2...Nc6/3. Bc4/3...g6/4. Qf3

=Parham Attack=

4. Qf3
White renews the threat of (delayed) Scholar's mate 5.Qxf7# if Black does not prevent this, for example, if 4...Nd4?? to attack the queen, or 4...Bg7?? or 4...d6??. Black’s options are to play 4...Nf6, which successfully blocks the checkmate threat.

Theory table
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'''1. e4 e5 2. Qh5 Nc6'''