Continuity mistake: When the pirates swears the oath to kill Dragon Mao, they drip blood on one of the pirate's hand. The blood stains on his hand differ between the shots. (00:02:50)
Audio problem: A punch thrown by Big Eddie during her fight makes a sound before it's even connected.
Continuity mistake: When Molly Ringwald is on the phone at the club and gets approached by the girl in orange, throughout the whole conversation the position of the phone receiver in Randy's hand is wildly inconsistent. (00:09:30 - 00:11:00)
Revealing mistake: A bunch of seedy individuals are gathered, weapons in hand. Unbeknownst to them, though, deadly ninjas are creeping by, with all the speed of fast-forwarded footage. The problem, besides how obvious the trick is, is that it also features a visible jump cut; you can see the foliage change position literally from one frame to the other during the same shot. (00:01:30)
Continuity mistake: The protagonist just flushed down the drugs a girl was selling in a bathroom stall. She threatens him saying "Someone's gonna come lookin' for you." In the next shot, the shadow she and the other poofy-haired girl by the stall project on the door tripled in size. (00:33:30)
Revealing mistake: When Paul Kersey blows up the restaurant, there are obvious dummies in the booth. (00:46:01)
Continuity mistake: A rectangular metal object inside the sandwich box magically appears seconds after Rowdy opens the sandwich box, only to disappear a shot later.