Two knights defence - Perreux variation
1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6 4. d4 exd4 5. Ng5
White moves the king's pawn to e4. Black moves the king's pawn to e5. White develops the knight to f3.
Black develops the knight to c6. White develops the light-squared bishop to c4. Black moves the knight to f6.
White advances the queen's pawn to d4. Black captures on d4 with the king's pawn. White jumps the knight to g5.