It is, for now. However, feels like he could totally continue improving the skills to a point where it's actually like "Oops, I actually can make people immortal now." Then the humans would go to war with each other over who gets to use him, and he'll have to be like "Nah, dudes" and return to being a threat for most of the greedy bigwigs. It'd be nice if this doesn't go down exactly like that.