Later...

: You could have defeated us, but that doesn't prove you're the real Cobra Commander. How could we know which one is the genuine article?

: Well, the fake Commander will not react the same as the real one at some point. He just looks like the Commander, just like Red Jackal and I are similar, but see this: blood...

: FOR THE BARON!

: Oh, I got it! What if you became a ssserpent?
Fake Commander: What's up with it?

: I wasss a man! Well, I'm a man again, but it provesss I'm the real Cobra Commander!