411 REFERENCE · Wikibooks
Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bc4/3...Bc5/4. d3/4...f5/5. Ng5
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Lucchini Gambit Lucchini Gambit
5. Ng5 · Lucchini Gambit
White chooses the aggressive 5. Ng5, eyeing an early attack on f7. This sharpens the game considerably and signals a tactical battle. Black must now decide how to respond to the dual threats of Nf7, forking the queen and rook, as well as Qh5+. If White is able to bring their queen, knight and bishop towards Black's weakened kingside, they'll be in trouble.
However, Black has 5...f4!, cutting off White's dark-squared bishop and threatening Qxg5, effectively inviting White to attack their f7 square.
Theory table
1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.d3 f5 5.Ng5
References