It's a decent puzzle idea, though needs some polish.
Stuff about the path of the green dot and resetting the enemies is already mentioned by other reviewers, so I'm gonna add one more suggestion: maybe change how the enemy rotating works as it's a bit fiddly now. I think you could do something like dragging the mouse and aiming the enemy at it (with snapping to the angles, as it is now).
Perhaps you could implement more content in the future, but overall, nice job!