So I put the difficulty slider all the way to the right to see just how hard it is there. I test it by summoning a Lich. I provoked it and guess what? I got killed in one shot by a lightning spell.
You think that's normal? Well, my character's a Breton, so I get 50% resistance to all magicka. Then I also have a 25% shock shield, and 380 HP. So, the original damage must be well over 1000, because I had 75% resistance to shock.