Chess Opening Theory/1. e4/1...c5/2. Nf3/2...d6/3. d4/3...cxd4/4. Nxd4/4...Nf6/5. Nc3/5...a6/6. Bg5/6...e6/7. f4/7...b5/8. e5/8...dxe5/9. fxe5/9...Qc7/10. exf6/10...Qe5/11. Be2/11...Qxg5/12. O-O/12...Qe5

=Polugaevsky Variation=

Moves : 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Bg5 e6 7. f4 b5 8. e5 dxe5 9. fxe5 Qc7 10. exf6 Qe5+ 11. Be2 Qxg5 12. 0-0 Qe5

Because of the menace 13...Bc5, White has to "lose" a tempo : /13. Kh1/ (main line)

Theory table
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'''1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Bg5 e6 7. f4 b5 8. e5 dxe5 9. fxe5 Qc7 10. exf6 Qe5+ 11. Be2 Qxg5 12.0-0 Qe5'''