Creepy Doll: One of the enemy types, a deformed doll that attacks much like the headcrab from Half-Life 2.

Creepy Child: The game's only real 'boss' fight is against three of these that look about the same.

The basement of the Abandoned Hospital, which is actually the game's last level.

Creepy Basement: The basement of Grey's house leads into a nightmarish asylum, somehow.

Conditioned to Accept Horror: Later in the game, one of Grey's messages states that the merging between the Dark World and real world at various points doesn't bother him anymore.

Cobweb Jungle: Sort of, some sections of the game will place a cobweb-like black substance in places like vents.

Body Horror: Many of the enemies encountered look very deformed, including the ones that look nearly human.

Beast with a Human Face: One of the enemies encountered is a strange dog-like monster with a disturbing humanoid face.

Barrier-Busting Blow: Happens during the 'asylum' hallucination from an enemy that can't be harmed.

Bad Black Barf: One of the enemies encountered uses this as its main attack.

Half life horror mod