Likely using means that are already outlawed, like blood magic or necromancy. Even then, I imagine it would require an unconscionable amount of power to achieve...especially without harming a mortal host.I fear how many people will be sacrificed for this.

[ Obviously, if Temperance has done this before, it won't be an unheard of feat. Still, it feels like an impossible task. ]

It's possible. It would mean destroying the ritual site, stopping the participants...

[ Likely killing the mortal vessel, if that's even how this is going to happen. What if it's a baby or a child? ]