Key ideas
- 5.Nc3 Qc7 is the modern main line. White often uses an English Attack set-up, 6.Be3 a6 7.Qd2 Nf6 8.O-O-O, and Black answers with 8...Bb4, pinning the knight and putting pressure on e4.
- Quieter systems with 6.Be2 or 6.g3 see White castle short and play f4 or a slow build-up, while Black develops with ...a6, ...Nf6 and ...Be7 or ...Bb4.
- 5.Nb5 d6 6.c4 is the Szén Variation, which sets up a Maróczy Bind. After 6...Nf6 7.N1c3 a6 8.Na3 Black usually plays ...Be7 and ...b6 for a hedgehog structure, and 8...d5 (the Gary Gambit) is a sharp alternative.
- The c6 knight gives Black options other Sicilians lack: an exchange on d4 to pull White's queen forward, ...Ne5 to hit a bishop on c4 or a queen on d2, and ...Bb4 pins against the c3 knight and e4.
Plans for White
Choose between space and attack. The Szén gives a slow, lasting space advantage; the English Attack with Be3, Qd2, f3 and long castling aims for a kingside pawn storm. In both, expect the d4 knight to be harassed and have b3 ready as a retreat square.
Plans for Black
Keep the position flexible: ...a6, ...Qc7 and ...Nf6 first, ...d6 only when needed. Look for ...Bb4 against e4, ...Ne5-c4 against a queen on d2, and queenside expansion with ...b5.
For the wider picture, see the Sicilian Defense guide.