Just a little FYI for those of you playing mages to try and save you a bit of a headache if you haven't maxed out destruction yet.

I'd advise staying away from lightning when levelling up the destruction tree if you are planning on having the 2 thralls from maxed out conjuration also. I just maxed out both trees with the destruction damage points in lightning earlier seeing as the lightning master spell is the only target-able and controllable one out of the 3 types. Worst move i could have made, lightning storm damages and Aggros the thralls meaning it either kills them or they turn around and kill you instead of the mobs. Neither Blizzard nor Firestorm damage them and i'm wishing i'd invested points in either fire or frost now instead.

Must admit it was kinda fun fighting my own pets in the college for a laugh then half the mages there decided they wanted a piece of me too lol.

I didn't figure it was practical so I didn't bother trying.

I tend to stick with Atronachs for this precise reason. They have an elemental immunity that can be exploited.