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* Cooper, the alien. Though he's not as scary as we think he is. He just wants to go home.
** Then again, he EATS PEOPLE. Which doubles the horror as you realize that it makes telepathic contact with everyone it touches, so it HAS to know its victims are frightened innocents...
** Not to mention he keeps his dinner hanging from spiderweb-like things underground beneath the watertower.
* The train crash and all of the aftermath, especially the OnlyMostlyDead teacher in the truck.
* [[{{Gorn}} Nelec's death]]. Seriously, how were they allowed to show that in a PG-13 movie?