Caissa Codex
E06

Catalan Opening: Closed 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 Catalan Opening: Closed

Play Black's moves of the line from memory — 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. g3 Bb4+ 5. Bd2 Be7 6. Bg2 O-O 7. O-O c6 8. Bf4 b6 — and the trainer plays White's replies; "Play the other side" turns it around.

Read about the line, its statistics on Lichess and Stockfish's evaluation on the Catalan Opening: Closed page, or pick another opening in the opening trainer.

https://chesscodex.org/train/catalan-opening-closed-6