Destruction is the only thing that can kill. Regeneration is for heals. Those are your primiary spellpools for fighting. The other pools are mainly for gimmicks as light, infravison, invisibility, feather, life detect and whatever else.
Have you really been all the way to that cave in the northlands? You should have a hard time getting there already, as everything on the way is 20+
if you follow the coast from Erothin until the Piratecave, there must be a stranded ship somewhere on the way.