Knights Variation

The Knights Variation of the Indian Defense arises after 1. d4 Nf6 2. Nf3. White develops the king's knight and leaves the c-pawn at home for now, so the choice of system can wait until Black has shown how the pieces will be developed. A player who is happy to face the King's Indian but wants to sidestep the Nimzo-Indian, for example, can answer 2...g6 with 3. c4 and 2...e6 with 3. Bg5. The position is also reached often from 1. Nf3 Nf6 2. d4. It ranks among the most frequently reached named positions in the Lichess database, engines consider it roughly balanced, and Black's results there are nearly level with White's.

Black's second move usually declares where the bishops are headed. The most popular reply, 2...g6, is the East Indian Defense, pointing toward King's Indian or Grünfeld setups. White can enter a King's Indian with 3. c4 or keep the c-pawn back with 3. g3, the Przepiorka Variation, 3. Bg5, the Torre Attack, or 3. Bf4, a London System. After 2...e6 the king's bishop looks to the a3–f8 diagonal, and besides the same four third moves White has 3. e3, a Colle-style plan called the Yusupov-Rubinstein System. 2...b6, the Pseudo Queen's Indian, and 2...d6, the Wade-Tartakower Defense, commit the queen's bishop or its pawn chain first instead.

Black can also stake a claim in the center at once. 2...d5 gives the Symmetrical Variation of the Queen's Pawn Game, from which 3. c4 transposes to the Queen's Gambit. 2...c5, the Spielmann-Indian, has a Benoni flavor; White normally either advances with d5 or supports the d4-pawn with c3 or e3. 2...c6, the Czech-Indian, tends toward Slav-type positions, as after 3. c4 d5.

The remaining replies are uncommon. 2...b5, the Polish Variation, discourages c4 and prepares ...Bb7, while 2...Ne4 is the Döry Defense. The only named sub-variation, the Alburt-Miles Variation 2...a6, is very rarely played, and White scores well against it in the database. In practice the Knights Variation is less a fixed line than a junction: its theory consists mostly of transpositions, and both sides use the move order to steer toward the structures they prefer.