Caissa Codex
D37

Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense, Blockade Line 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 Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense, Blockade Line

Play White's moves of the line from memory — 1. d4 Nf6 2. c4 e6 3. Nc3 d5 4. Nf3 Be7 5. Bf4 O-O 6. e3 Nbd7 7. c5 — 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 Queen's Gambit Declined: Harrwitz Attack, Two Knights Defense, Blockade Line page, or pick another opening in the opening trainer.

https://chesscodex.org/train/queens-gambit-declined-harrwitz-attack-two-knights-defense-blockade-line