Marcus was originally supposed to be killed by being thrown off the roof of a building by Hoax. However, this had to be changed to Marcus getting killed in the bathroom by Hoax instead because of the low budget.
When Spike is dialing from a phone booth outside the auto parts store, his is instructed to dial "666." He pushes three buttons, but the final tone is a different frequency than the first two. If he dialed three sixes, all three tones should have been the same.
When the girlfriend is preparing a tv dinner in her home, she puts the dinner in the oven then puts the timer on 25 minutes, but when they do a close up of the clock, it says 15 minutes.
Pet Parrot:
[After possessed Hoax slashes and kills his mother and blood splatters onto the sofa]
[Repeated Line]
Pet Parrot:
Not on the couch! Not on the Couch! *squawk
Hoax: [Possessed Hoax reaches into the cage and squeezes the bird to death]
That's what the plastic's for, asshole!
What are the differences between the Theatrical Version and the Extended Cut?
A
In the US, Robert Englund's solid debut as a director was 14 minutes shorter in movie theaters. This version is knows as "Cinema Cut" and it misses some smaller and some bigger plot elements but most of them are completely superfluous so I take it the footage was removed for pace reasons. A longer "Extended Version" was released on VHS and Laserdisc. As a detailed comparison shows, the Laserdisc Version is based on the Extended Version and yet it's not completely uncut - as this comparison shows. Whether or not the VHS is completely uncut is unknown. The DVD only contains the "Cinema Cut", a decent release of the "Extended Cut" hasn't been announced yet. In Germany, both the "Cinema Cut" and the "Extended Version" are available on the DVD released by Eyecatcher Movies. The VHS wasn't uncut either by the way. A detailed comparison between both versions with pictures can be found here.