ECO A04: Zukertort Opening, Modern Defense & more

ECO A04 is part of volume A, Flank Openings. The Lichess chess-openings dataset files 31 named lines under it, from 4 different openings. The shortest is Zukertort Opening: 1. Nf3.

That position has come up in 93,377,152 Lichess games between players rated 1600 to 2500: White won 50.8%, 5.6% were drawn and Black won 43.7%.

Opening	Moves	Games	Length
Zukertort Opening	`1. Nf3`	93.4M	1 move
Zukertort Opening: Arctic Defense	`1. Nf3 f6`	215K	1 move
Zukertort Opening: Basman Defense	`1. Nf3 h6`	140K	1 move
Zukertort Opening: Black Mustang Defense	`1. Nf3 Nc6`	6.1M	1 move
Zukertort Opening: Dutch Variation	`1. Nf3 f5`	1.8M	1 move
Zukertort Opening: Herrstrom Gambit	`1. Nf3 g5`	115K	1 move
Zukertort Opening: Kingside Fianchetto	`1. Nf3 g6`	4.4M	1 move
Zukertort Opening: Pirc Invitation	`1. Nf3 d6`	4.7M	1 move
Zukertort Opening: Polish Defense	`1. Nf3 b5`	148K	1 move
Zukertort Opening: Queen's Gambit Invitation	`1. Nf3 e6`	7M	1 move
Zukertort Opening: Queenside Fianchetto Variation	`1. Nf3 b6`	2.2M	1 move
Zukertort Opening: Ross Gambit	`1. Nf3 e5`	1.9M	1 move
Zukertort Opening: Sicilian Invitation	`1. Nf3 c5`	10M	1 move
Zukertort Opening: Slav Invitation	`1. Nf3 c6`	3.8M	1 move
Zukertort Opening: St. George Defense	`1. Nf3 a6`	188K	1 move
Zukertort Opening: Ware Defense	`1. Nf3 a5`	63K	1 move
Zukertort Opening: Lisitsyn Gambit	`1. Nf3 f5 2. e4`	222K	2 moves
Zukertort Defense: Kingside Variation	`1. Nf3 Nh6 2. d4 g6`	9,857	2 moves
Zukertort Defense: Sicilian Knight Variation	`1. Nf3 Na6 2. e4 c5`	9,048	2 moves
Zukertort Opening: Drunken Cavalry Variation	`1. Nf3 Na6 2. e4 Nh6`	5,210	2 moves
Zukertort Opening: Vos Gambit	`1. Nf3 d6 2. d4 e5`	296K	2 moves
Zukertort Opening: Wade Defense	`1. Nf3 d6 2. e4 Bg4`	513K	2 moves
Zukertort Opening: Lisitsyn Gambit Deferred	`1. Nf3 f5 2. d3 Nf6 3. e4`	58K	3 moves
Zukertort Opening: Speelsmet Gambit	`1. Nf3 c5 2. d4 cxd4 3. e3`	53K	3 moves
Zukertort Opening: Arctic Defense, Drunken Knight Variation	`1. Nf3 f6 2. e4 Nh6 3. d4 Nf7`	10K	3 moves
Zukertort Opening: The Walrus	`1. Nf3 e5 2. Nxe5 Nc6 3. Nxc6 dxc6`	203K	3 moves
Colle System: Rhamphorhynchus Variation	`1. Nf3 c5 2. e3 g6 3. d4 Bg7 4. dxc5 Qa5+`	14K	4 moves
Modern Defense: Semi-Averbakh Variation, Polish Variation	`1. Nf3 c5 2. c4 g6 3. d4 Bg7 4. e4 Qb6`	5,250	4 moves
Modern Defense: Semi-Averbakh Variation, Pterodactyl Variation	`1. Nf3 c5 2. c4 g6 3. d4 Bg7 4. e4 Qa5+`	4,904	4 moves
Zukertort Opening: Shabalov Gambit	`1. Nf3 e6 2. c4 a6 3. Nc3 c5 4. g3 b5`	365	4 moves
Modern Defense: Semi-Averbakh Variation, Pterodactyl Variation Accepted	`1. Nf3 g6 2. d4 Bg7 3. e4 d6 4. c4 c5 5. dxc5 Qa5+`	6,753	5 moves