In this movie clip, there's this conversation between Monkey and Beetle, starting at 50 seconds into the clip:
Beetle: Well, fast learner. Did you know you could do that?
Monkey: Show off.
The context is that while Monkey and Beetle were arguing, Kubo made a boat.
What did Monkey mean by "Show off"?
If interpreted as an imperative mood, it doesn't really make sense to me.
If it's not, what is it?