Ensara:
"Well to clarify if I was actually taking the deal, I'd be screwing him over. Straight up. Like my plan would be to basically make a ritual, super-lie to him that that it will free him when all it would really do is like, allow me to devour him using certain Metagaos charms and turn him into one of my component souls and thus whatever entity remaining would be loyal to me. The deal would technically be fulfilled since Tzeentch would become me in a sense, and thus since I would be free and he would be apart of me well....technically fulfilled but not his favor.

But I can see why that you wouldn't want even that. not sure if a god-devouring charm would work on him without a perk."