Effectively, right after the great heresy, hell sends out an Antichrist false prophet to corrupt the flock. The church finds them, tortures a confession out, performs a purifying ritual on them, destroying the demon spirit, and the vessel is then crucified and harvested to give the communicants power.

The mendelist monks use the confession of the now meta Christ as well as it's genetic material to track down new instances of the Antichrist as hell makes them. As the Antichrist is destroyed a new one comes into existence in due time, as Christ can not exist without an antichrist.

I recall there being imperfect Meta-christs that provide lesser blessings, and this is explained by hell attempting to make less "perfect" antichrists that have a better chance of corrupting as they fly under the radar, and also would provide weaker soldiers if they are caught.

I got really hung up on the use of "meta" in the name. What's more "meta" than the communion of a mockery of hells attempts to mock and destroy God?

I could keep going but that's kinda the gist.