This.

Sadly, Skyrim has too few of these actual bosses in the game. You can beat all of them on the first encounter.

If you can't, change difficulty to novice and you will guaranteed be able to kill him.

That happened the second time I beat him. I had positioned Ahtar the Jailor right next to him with an ebony greatsword and he died without a fight.

Spellbreaker shield, 100 block and all perks up left side. Dragon preists no longer a problem, or an magic weilder for that matter.
You can stand and have a coffe break while holding up the sheild and wait till your finished and kill him, or wait till whenever killing him takes your fancy.

I had same problem. There is a programming glitsch. Sometimes when you go back for another fight the priest just hangs there, passive. You can then take him out in seconds. It,s purely random, but on my fourth try, he was hanging there and I killed him.

Another technique is to back him into the small pond at the back of the dungeon. Sometimes he gets stuck and can be taken down easily. This is hard to do.

But on the first option, it's your only chance if you are less than lvl 15.

Exactly, there are too few fights like this. This game needs beefed up combat across the piece.

Yes, happened to me. It,s a random bug. All you can do is take advantage of it.

Great bows did it for me this time (Breton with lots of resistance perks - have Lord stone, and Agent of Mara)... But with my bow skills and level, he barely touched me. Last time i was a High Elf and had great melee weapons.... bum rushed him as soon as the shield went down. Plan it all before you start. take as many buffing potions, have the right weapons.... you can do it at 20.

I killed him at level 17 or so - if you have the Wabbajack, just use that over and over ...

Wabbajack for sure! And don't go in the room. Shoot him from outside. That way you can duck back and regroup.

I just faught him though my char is over lvl 50 but i play on expert difficulty, i would recomend the Slow Time shout if you have it

I play on expert and trust me exploring a random dungeon took my 5 tries to complete and i kept getting killed at the exact same spot, but thank god for slow time shout, thats going to be my answer for everything now, its the best shout in the whole game

This^. Bring lots of magicka potions, summon early and often, and hit him with ranged attacks.

there are 40% resist shock boots in the archmages room

first of all the weapons dropped by the draugr getting to him sem to work best on him.

i always use the bow to take out the mages first and then use it on him.

it may take some time but you will defeat him.

I beet him pretty easy with the impart perk and a lot of magic potions

Seriously, stealth and steel arrows. And patience...

Bring friends. Friends you don't mind losing. Lots of friends (assuming on PC and using mod like UFO).

Seriously though on an early playthrough I think I took him on around 12-15 using an archer (thief/mage). Hide in shadows, killed him with bugs bites. Took quite a long time from what I remember. Just took 1-3 pot shots at long range, then move while in stealth mode to another location - NPC AI only seems to look where the shot came from, not search the surrounding area. Another time took him on as a pure mage, but as I stated at the top, I had a friend with me - Cosnach, who actually survived. (Both of these when I was playing on the 360).

I beat him at level 8, but only because his AI svcks. He stood in the passage to the main chamber and didn't attack me while I pelted him with arrows. Took about 100 iron arrows or so.

That must've been awfully painful for him. That's a shame.

I wish they would have showed them all

That would be awesome, he'd look like a pincushion
Some awesome advice/tactics here guys, thanx

I've beat him a couple of ways.
1) A couple of fire balls from the door. Close the door and recharge/heal when needed. Then repeat.
2) Get under the bridge. If he goes one side of the bridge, you go other. If he comes down, you go up. Switch back and forth so you can always get out of the line of sight. Then summon atronach's for help. When he starts fighting the atronach, step out and take a couple of shots at him.