Nimzowitsch Defense: Kennedy Variation, Paulsen Attack

The Nimzowitsch Defense: Kennedy Variation, Paulsen Attack 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 4 moves: 1. e4 Nc6 2. d4 e5 3. dxe5 Nxe5 4. Nf3. The resulting position leaves black to move.