Speed: Bullet to Correspondence Rating:
Alekhine Defense: Two Pawns AttackBETA
Black saves their Knight which was attacked by the pawn on c4. This move is not seen as best because the Knights position on b4 is unstable, it will likely have to move back to either a6, where it will be on the edge of the board, or c6, where it will block the other knight's most natural square.
This move can lead to a wide variety of positions, depending on how the game develops.