I always found the area of effect poisons he is using very worrisome when he's not soloing. Didn't he have to gain poison immunity to not be accidentally poisoned by his own magic? Now he has a weak and injured ally. How much you want to bet the author is going to forget his own world building and have him use poison magic on the baddies, never mind the potential friendly fire killing your NPC your supposed to being escorting to safety.