Three knights - Schlechter variation
1. e4 e5 2. Nf3 Nc6 3. Nc3 Bb4 4. Nd5 Nf6
White pushes the king's pawn to e4. Black pushes the king's pawn to e5. White develops the knight to f3.
Black develops the knight to c6. White moves the knight to c3. Black develops the dark-squared bishop to b4.
White moves the knight to d5. Black moves the knight to f6.