Zukertort Opening: Arctic Defense, Drunken Knight Variation is a chess opening with the ECO code A04, part of the Zukertort Opening family. It goes 1. Nf3 f6 2. e4 Nh6 3. d4 Nf7. White opens with 1. Nf3 (the Zukertort/Réti knight move) and Black answers 1... f6. After 6 moves it is White to move. The lesson on the board explains every move of the line and lets you play it yourself; it is free.
The moves
1. Nf3 – White plays the knight to f3
1... f6 – Black plays the pawn to f6
2. e4 – White plays the pawn to e4
2... Nh6 – Black plays the knight to h6
3. d4 – White plays the pawn to d4
3... Nf7 – Black plays the knight to f7
About the Zukertort Opening
White starts with 1.Nf3, a flexible move that develops and controls e5 and d4. White can later go into many different openings.
It stops ...e5 for now and keeps d4 or c4 options open.
Common follow-ups are g3, Bg2, O-O (a King's Indian Attack style).
Black can take the centre with ...d5 and ...c5; react calmly.
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