Legendary Ancano

[danconnors]

On legendary difficulty it's about impossible to kill Ancano. Before I drop the difficulty to normal to finish him off, any suggestions on what to do with him in legendary mode?

[Trigger]

use ice form shout, freeze him first then hack him up

[Gropax]

slow time works well too

[DFH01]

Dremora Lord is about the best way to go with that, you deal with the eye, let the Dremora deal with Ancano..

[perico2palotes]

Your best bet is likely summon a high vitality monster, then muffling yourself then going invisible until the Eye of Magnus opens and you can shoot it with the staff. That's when Ancano becomes vulnerable. Then you can try using paralyze poisons (they should probably work at this point) or paralyzing weapons, plus stacking resist magic effects, like general resist magic effect then a resist frost / fire / electricity potion (those apply two different layers of protection).
No matter what type of toon you are, healing potions are very strong because you can pause the game and go to full health even if you're being knocked down by an enemy's Unrelenting force shout. Blue mountain flower + wheat are dirt cheat potions you can make that both restore health and fortify health. Fortify health has saved my bacon when tackling legendary elder dragons while being level 30-ish (on legendary, at armor rating ~310 and 400-ish health, an elder dragon can one-shot your toon at 70% health).

[danconnors]

Too late! I set the game on easy long enough to finish Ancano off. My summoned Daedric dummy was bashing on the flying soul gem holders, as were all the useless mages. My armor is fortified (double fortified) against fire, cold, and shock to about 100% for each type, so I was holding my own pretty well. But as soon as I would take off after Ancano myself, he'd reopen the eye.

I've killed revered dragons on legendary and they went down a lot easier.