This page covers the King's Indian setups that White meets before the classical main lines: 1.d4 Nf6 2.c4 g6 with Nf3, e3, g3 or a quick Nc3, and Black's flexible ...Bg7, ...d6 and ...O-O. Black often adds ...Nc6 to pressure d4, and White's typical reply is d5, gaining space with tempo. Many of the mistakes come from that one pawn push.
The most common one is ignoring it. In a line that starts 1.Nf3 g6 2.d4 Bg7 3.c4 d6 4.Nc3 Nc6 5.e3 Nf6 6.Be2 O-O 7.O-O Nd7 8.d5, Black plays 8...e5?, and the knight on c6 is simply lost to 9.dxc6. After a d5 push the knight must move at once, unless capturing en passant is possible.
Moving the knight to the edge is not always safe either. After 1.d4 Nf6 2.c4 g6 3.e3 d6 4.Nf3 Bg7 5.Nc3 O-O 6.Be2 Nc6 7.O-O Bd7 8.d5, the jump 8...Na5? attacks c4, but after 9.b4 Nxc4 10.Bxc4 Black has only a pawn for the knight.
White makes one-move mistakes too. After 1.d4 Nf6 2.c4 g6 3.Nf3 Bg7 4.g3 d6, the bishop sortie 5.Bh6?? simply hangs: 5...Bxh6. In another line, 7.O-O Qa5 is met by 8.b3??, which takes away the only defender of the knight on c3: 8...Qxc3. And Black's 7...Bg4?? against h3 drops the bishop to 8.hxg4.
These are basic tactics, but they appear in real games between players rated far above beginner level. The King's Indian Defense study explains the main lines and plans; the puzzles below train the patterns that decide the early middlegame.
| Mistake | Side | Count | Avg loss |
|---|---|---|---|
| 8.e5 | White | 7 | 5.4 pawns |
| 8.Na5 | White | 4 | 2.9 pawns |
| 5...Bh6 | Black | 3 | 8.3 pawns |
| 8...b3 | Black | 3 | 3.7 pawns |
| 7.Bg4 | White | 3 | 7.2 pawns |