Caissa Codex
C60

Ruy Lopez: Cozio Defense, Paulsen Variation 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 Ruy Lopez: Cozio Defense, Paulsen Variation

Play Black's moves of the line from memory — 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nge7 4. Nc3 g6 — 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 Ruy Lopez: Cozio Defense, Paulsen Variation page, or pick another opening in the opening trainer.

https://chesscodex.org/train/ruy-lopez-cozio-defense-paulsen-variation