Continuity mistake: When Mugatu is holding the bomb, the bomb constantly switches from his right hand to his left hand throughout the scene.
Continuity mistake: Penelope Cruz's mole switches sides several times during the film. (00:04:03 - 00:57:55)
Continuity mistake: When Justin Bieber takes out his phone after being shot, the time on the phone is displayed as 1:48AM, but seconds later, when the camera pans down on the phone before the scene ends, the time displayed on the phone is now 1:51AM. Three minutes did not pass during this time.
Answer: Mugatu was killed when the bomb was hurled back at him.
raywest ★