Sicilian Defense: Scheveningen Variation, Delayed Keres Attack, Perenyi Gambit

The Sicilian Defense: Scheveningen Variation, Delayed Keres Attack, Perenyi Gambit is a chess opening classified under ECO code B90 in the Semi-Open Games family, where Black responds to 1.e4 with something other than 1...e5, including the Sicilian Defense, Caro-Kann, and Pirc. It is reached after 9 moves: 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be3 e6 7. g4 e5 8. Nf5 g6 9. g5. The resulting position leaves black to move.