FFT's Vormav.

He personally puts his country into a civil war to raise the in-universe equivalent of Satan from the dead, which simply involves getting enough people killed. He does this from the FFT Vatican and winds up killing the FFT Pope.

Did I mention he involves his only two children in the plot by throwing them in front of the main character, fully expecting him to kill them? Because he does, and Ramza winds up killing one of them. He has no remorse over this.