The Antichrist was a figure associated with the apocalypse, often heralded by prophecies. (PROSE: White Canvas)
Rick Kithred originally believed Godfather Avatar to be the Antichrist before later reversing his view and considering him to be God. (PROSE: Of the City of the Saved...)
Cousin Gideon of Faction Paradox (PROSE: A Bloody (And Public) Domaine) had an interest in "potential Antichrists", claiming he had met "a few (…) in [his] time". He grew particularly interested in the Hollow Childe, a prophesied potential Antichrist. (PROSE: White Canvas) Her prophecy stated:
The Hollow Childe Will Stand at the End of the Universe, Laughing Amidst the Tears...
She was reportedly half-human and half-demon, "a husk with an insatiable appetite for death" who would embody and bring about "the endless shadow at the end of all things". Her powers manifested from an early age, including the ability to hover, spit blood from her mouth, and leak "black fluid" from her eyes. However, she had yet to unlock her full power. A group of cultists amassed around her and tried to speed the process along by committing mass, ritualistic suicide, despite the Childe trying to talk them out of it.
The slaughter had no effects, but did allow Gideon to find the Hollow Childe. He brought her to Auteur's Town to try and educate her in how best to use powers, but over the years, the Hollow Childe was befriended by Citizen 176 and Graelyn Scythes and grew into a compassionate person who wanted to use her powers for good and had no desire to bring about the end of the universe. Gideon was enormously upset about this, and believed that Auteur had deliberately allowed this to happen and "ruined the Antichrist" because she was jealous of her cousin's protégé and, as always, felt a pathological need to "break everyone else's toys" because she "thought hers were nicer". (PROSE: White Canvas)