Chess Opening Theory/1. d4/1...Nf6/2. c4/2...Nc6/3. Nf3/3...e6

=Black Knights Tango=

3...e6
Black has a solid and flexible formation. The e6 pawn opens a line for the Black Bishop allowing a possible Bb4 which can transpose into a Nimzo Indian or a Bogo Indian defence. White's possible moves include playing a3 immediately to prevent Bb4 as well as development moves, Nc3, g3 and e3.

Theory table
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'''1. d4 Nf6 2. c4 Nc6 3. Nf3 e6'''