Chess Opening Theory/1. e4/1...Nc6/2. Nc3/2...e5

Vienna Game, Max Lange Defence (transpose from Nimzowitsch)
White has a couple of good options here, see the theory table below.

The Vienna Gambit /3. f4/ exf4 4. Nf3 g5 often leads to White sacrificing a knight on f3 or a bishop on f7.

3. Nf3 transposes to the Three Knights Game.

Theory table
1. e4 e5 2.Nc3 Nc6