Caissa Codex
A48

London 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 London System

Play White's moves of the line from memory — 1. d4 Nf6 2. Nf3 g6 3. Bf4 Bg7 4. e3 — and the trainer plays Black's replies; "Play the other side" turns it around.

"Drill all" adds the 5 named lines that continue it, such as London System, with Be2, London System, with Bd3.

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

https://chesscodex.org/train/london-system-2