Sicilian Defense, Four Knights Variation

The Four Knights Variation is identified when White's knights stand on d4 and c3 while Black's knights occupy c6 and f6. The name describes this specific arrangement of four developed knights, not a special rule or tactical pattern.

Black attacks the central squares, especially d4, e4, d5, and e5, with pieces before deciding whether to advance the d-pawn or the a-pawn. That flexibility allows different move orders to reach positions resembling other Sicilian systems. A transposition is the arrival at the same position through a different sequence of moves.

White can increase pressure on c6, move a knight to b5, or complete development, meaning bring the bishops out and prepare king safety, with Be2, Be3, or other ideas. Black must pay close attention to d5 and b5, but gains active pieces and has committed fewer central pawns than in many other variations.

The line is not necessarily quiet. After Ndb5 and ...d6, play can become highly dynamic. Exact move order also matters: 2...a6 defines the O'Kelly Variation, even if the knights later reach similar squares.