Queen's Indian Defense: Fianchetto Variation, Check Variation

The Queen's Indian Defense: Fianchetto Variation, Check Variation is a chess opening classified under ECO code E15 in the Indian Defences family, where Black responds to 1.d4 with 1...Nf6, including the Nimzo-Indian, Queen's Indian, and King's Indian. It is reached after 5 moves: 1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. g3 Ba6 5. b3 Bb4+. The resulting position leaves white to move.