Chess Opening Theory/1. d4/1...Nf6/2. c4/2...Nc6/3. Nc3/3...e6

=Black Knights Tango=

3...e6
Opening the diagional for the Black Bishop to develop and supporting d5.

Theory table
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'''1. d4 Nf6 2. c4 Nc6 3. Nc3 e6'''