- Unnamed Wild Magic Soul-Stealing Spell: A powerful spell that Cure Elim used to steal the souls of all living things within 250 kilometers, and turn them into zombie thralls under his full control. It affected four entire countries at once due to its gigantic radius. However, powerful beings are able to resist the effect for a short time before succumbing.
If it can be resisted, it means it is not infinitely powerful, and this power can be measured. In this context, you don't need a WCI, just being powerful enough makes you resist the spell, but
how powerful?
As it is stated in the Resistance page, a character without a soul, for example, would obviously be immune to soul manipulation. Ainz isn't immune, he just has resistance to it that comes from his WCI. A resistance that is as powerful as Soulbreaker Breath.
I'm using Cure Elim's AP (City Level) because that's the power of all his stuff. Just because Soulbreaker Breath ignores conventional durability doesn't mean its more potent than his other spells, just that it can ignore conventional durability.