Since... 1994!

Four Knights Opening

1. e4 e5 2. Nf3 Nc6 3. Nc3 Nf6 4. Bb5 Bb4 5. O-O O-O 6. d3 d6 7. Bg5 Bg4 8. Nd5 Nd4 9. Nxb4 Nxb5 10. Nd5 Nd4 11. Qd2 Qd7 12. Bxf6 Bxf3


Then What? How should white move, to make black stop copying his moves?

Solution