Complete Monster: The Caretaker is a demonic entity who targets a group of teens who believe they had killed a man. She implants Neil with a lethal tumor that manipulates his mind, forcing him to send the group a chain letter telling them to perform tasks that will eventually damn their souls. When Neil fights his possession upon being told to burn down his school, the Caretaker leaves him to die. Targeting the survivors a few months later, the Caretaker gives Fran and Kipp outrageous demands that will never be met, then brutally kills them, with Fran being decapitated and Kipp being lit on fire. Posing as a nurse named Sasha, the Caretaker sabotages Alison's relationship with Tony, who she puts under Mind Control. When Alison discovers the truth, the Caretaker gleefully orders Tony to kill her, gloating that even if Alison stops her, another Caretaker will take her place.
Moral Event Horizon: Chain Letter 2 is all about invoking this trope. Each of the protagonists is given a task to complete which will push them over the horizon. If the task is not completed, the character in question will be killed, effectively giving each of them the choice between death and damnation. The tasks given ranged from the truly horrific ( Kip's was to set his younger sister on fire and ensure her entire right arm was burned) to the Felony Misdemeanor? ( Brenda cutting off her own finger and delivering it to one of the other characters was definitely a moment of Squick, but it's hard to see it as something worthy of eternal damnation).
It wasn't so much about "eternal damnation" in the usual sense as it was about what would be personally damning to each person who had to complete the task. Kip's task was to set his younger sister on fire and ensure her entire right arm was burned, but this would be personally damning because Kip loves his younger sister like fury, so Kip rather angrily refuses to harm the person he loves most. So the killer sets Kip on fire instead, but Kip's death is evidently preferable to what the killer was asking him to do. Meanwhile, Brenda is a person who loves her own body and her own physical beauty and attractiveness more than anything else. So cutting off a finger would be personally damning to her, but unlike Kip, Brenda is afraid of death more than she's afraid of disfiguring the thing she loves most, so Brenda gets drunk enough to cut off her finger without too much pain.
