Batman: Mask of the Phantasm (1993)

Continuity mistake: During Batman and Joker's fight, Batman kicks out one of Joker's teeth. Later on when Joker puts on his jet pack and starts to take off, he has all of his teeth. But in the next shot his tooth is missing again.

Continuity mistake: When Andi comes to Bruce's house for the first time and Bruce is practicing jujitsu, he trips Andi. When she hits the ground she is wearing a sweater, but before she was wearing a sleeveless blouse.

Continuity mistake: After Bruce proposes to Andrea and he drops her off at home, she is wearing the ring on her left hand when she is inside his car. But once she steps out of it, the ring completely disappears.