Caissa Codex
B50

Sicilian Defense: Kopec System trainer

Back to the opening, all openings to practise or my repertoire

Type a move and press Enter: e4, Nf3, O-O, or from and to squares like g1f3 (e7e8q to promote). The board is also played with the mouse.

Practise the Sicilian Defense: Kopec System

Play White's moves of the line from memory — 1. e4 c5 2. Nf3 d6 3. Bd3 — and the trainer plays Black's replies; "Play the other side" turns it around.

Read about the line, its statistics on Lichess and Stockfish's evaluation on the Sicilian Defense: Kopec System page, or pick another opening in the opening trainer.

https://chesscodex.org/train/sicilian-defense-kopec-system