English Opening: Symmetrical, Four Knights Variation

1.c4 c5 2.Nc3 Nc6 3.Nf3 Nf6 4.g3 d5 5.d4 e6 6.cxd5 Nxd5 7.Bg2 cxd4 8.Nxd4 Nxc3 9.bxc3 Nxd4 10.Qxd4 Qxd4 11.cxd4