Nimzowitsch Defense: Woodchuck Variation

The Nimzowitsch Defense: Woodchuck Variation is a chess opening classified under ECO code B00 in the Semi-Open Games family, where Black responds to 1.e4 with something other than 1...e5, including the Sicilian Defense, Caro-Kann, and Pirc. It is reached after 2 moves: 1. e4 Nc6 2. d4 a6. The resulting position leaves white to move.