When Lance is trying to start a car he finds, the wound on his right hand seems so severe he can't use it. However, after Lance enters the supermarket a few minutes later, the wound has completely vanished.
Lance climbs down a pipe from a rooftop and exposes a blue and black string thong. Later, when crawling on top of a bus, he is wearing boxer briefs.
Lance injures his right hand to the point that it is bloodied, and is unable to turn a key in a car ignition, but in the scene where he's on top of the school bus his hand is fine and has no visible injury.
In one scene the character Lance has a cut hand which inhibits his ability to start a car and escape from a zombie, in the next scene when he is safely in a grocery store his hand is perfectly fine.
When Lance is on all fours atop the bus, just before he steps down onto the hood of the car, the background just to the left of Lance's head shifts revealing a glaring editing mistake.