Philidor - Nimzovich - Locock variation
1. e4 e5 2. Nf3 d6 3. d4 Nf6 4. Ng5
White moves the king's pawn to e4. Black moves the king's pawn to e5. White develops the knight to f3.
Black pushes the queen's pawn to d6. White plays the queen's pawn to d4. Black develops the knight to f6.
White transfers the knight to g5.