ECO D02: Queen's Pawn Game, Queen's Gambit Declined & more

ECO D02 is part of volume D — Closed & Semi-Closed Games. The Lichess chess-openings dataset files 14 named lines under it, from 3 different openings. The shortest is Queen's Pawn Game: Zukertort Variation: 1. d4 d5 2. Nf3.

That position has come up in 61,296,521 Lichess games between players rated 1600 to 2500: White won 51.1%, 5.6% were drawn and Black won 43.3%.

Opening	Moves	Plies
Queen's Pawn Game: Zukertort Variation	`1. d4 d5 2. Nf3`	3
Queen's Pawn Game: Anti-Torre	`1. Nf3 d5 2. d4 Bg4`	4
Queen's Pawn Game: Chigorin Variation	`1. d4 d5 2. Nf3 Nc6`	4
Queen's Pawn Game: Krause Variation	`1. d4 d5 2. Nf3 c5`	4
Queen's Pawn Game: Symmetrical Variation	`1. d4 d5 2. Nf3 Nf6`	4
Queen's Pawn Game: London System	`1. d4 d5 2. Nf3 Nf6 3. Bf4`	5
Queen's Pawn Game: London System, with e6	`1. d4 d5 2. Nf3 e6 3. Bf4`	5
Queen's Pawn Game: Symmetrical Variation, Pseudo-Catalan	`1. d4 d5 2. Nf3 Nf6 3. g3`	5
Queen's Pawn Game: Zilbermints Countergambit	`1. d4 d5 2. Nf3 Nf6 3. c4 b5`	6
Queen's Pawn Game: Chandler Gambit	`1. d4 d5 2. Nf3 c5 3. g3 cxd4 4. Bg2`	7
Queen's Gambit Declined: Baltic Defense, Pseudo-Slav	`1. d4 d5 2. Nf3 Bf5 3. c4 e6 4. Nc3 c6`	8
Queen's Pawn Game: Levitsky Attack, Euwe Variation, Modern Line	`1. d4 d5 2. Nf3 c6 3. Bg5 h6 4. Bh4 Qb6`	8
London System: Poisoned Pawn Variation	`1. d4 Nf6 2. Nf3 d5 3. Bf4 c5 4. e3 Qb6 5. Nc3`	9
Queen's Pawn Game: London System, Pterodactyl Variation	`1. d4 g6 2. Nf3 Bg7 3. Bf4 c5 4. c3 cxd4 5. cxd4 Qa5+`	10