Moral Event Horizon
= the action that marks an antagonist as irredeemably evil; once past this point, redemption is no longer an option for the character and any explanation they may have had for villainy no longer excuses it
not all villains have such a moment, but once they do they are considered "pure evil"
moment must be played seriously and does not include humor to soften the blow
onward, all ambiguity surrounding the character's moral standing is resolved and can not be seriously questioned again by all in-the-know of the event
any attempt at redemption is not enough, fails, is interrupted, and/or ends in the death of the villain
depending on genre-typical expectations of violence/morals, the action can have very different degrees of evil
typical examples: killing a fan-favorite character, animal abuse, sexual assault, bigotry, betrayal, infidelity, domestic abuse, hurting the innocent and vulnerable
Examples from popular media:
Ego giving Starlord's mother the tumor that killed her (Guardians of the Galaxy Vol. 2)
President Coin dropping bombs on the evacuating children and killing Prim (Hunger Games)
Scar refusing to help Mufasa and throwing him into the stampede (Lion King)








