Starting from 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.Nf3 d6 5.g3 0-0 6.Bg2 c5, players enter the King's Indian Defense: Fianchetto Variation, Yugoslav Variation, Rare Line — ECO E64. With 220,388 games on record, the patterns below come from the largest practical sample available.
History and Notable Players
It arises from the King's Indian Defense: Fianchetto Variation, Delayed Fianchetto. Among the most prolific White practitioners are Jan Hein Donner (11 games), Miguel Najdorf (11 games), Gideon Stahlberg (9 games). Black-side regulars include Svetozar Gligoric (24 games), Diego Flores (9 games), Robert E Byrne (9 games).
Performance Across Rating Levels
The picture changes a lot as you climb the rating ladder. At 1200 Elo, the opening shows up in 0.00% of games (4,893 samples). White scores 50.6%, Black 45.1%, draws 4.3%. At 1800 the opening surfaces in 0.01% of games; White wins 49.7%, Black 44.8%, draws 5.6%. At 2500, 0.05% of games go into this opening; draws sit at 10.4% — the line is well-mapped at this level. Positions also become less sharp as level rises (sharpness 0.96 → 0.90).
Move Diversity and Theory Depth
What players actually play after the opening moves depends heavily on rating. At 1200 Elo (4,883 games), the top reply is d5, played 39.2% of the time. Three other moves each take at least 5% of games, and the top three moves account for 79.1% of games. Entropy: 2.36. By 2500 (6,151 games), O-O takes over as the top reply at 68.4%; only two other moves still reach 5% and the top three moves account for 98.8% of games. Entropy drops to 1.27. The narrowing is significant — strong players consolidate around a small set of best moves, while amateurs scatter across many plausible-looking options.
Main Lines and Variations
From the position after 1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.Nf3 d6 5.g3 0-0 6.Bg2 c5, the recognised continuations are:
Each branch leads to a different middlegame character — the resulting pawn structure decides what kind of game you get.
Common Mistakes
- Drifting away from main theory — At 400 Elo, the three most-played moves cover 78.5% of games, against 88.9% at 2000. The most popular deviation is dxc5 (played 20.5% of the time at 400, much less so up top). It looks fine but quietly hands the better-prepared side an edge.
- Neglecting development — It can feel productive to make extra pawn moves early, but falling behind in piece development is what loses most amateur games — especially in open positions where active pieces find squares fast.
- Letting White own the centre — Hypermodern openings concede central space on purpose, but only if you strike back in time. Delay the counter-blow and you end up squeezed.
Practice on Chessiverse
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