I just soloed rhag'zhezum (rhag1) in ssra.
The fight took just about 30 minutes (29:54.) I ended the fight full mana - I did accidentally hit spiritual channeling (shaman ability that lets you cast from your hps) towards the end (like last minute) of the fight, but I would have ended over 95m anyway.
Rhag1 is permarooted. He summons, however, only every 12 seconds or so. Run off during the time in betwee summons, and he ends up not doing too much melee damage.
Permarooted mobs have another odd mechanic. Normally-rooted mobs will attack your pet if you're out of range and it is, even if you have more aggro than your pet. This isn't true with permarooted mobs. If your aggro > pet aggro, then pet can be in melee range without getting hit, even if you aren't getting hit.
Towards the end, I realized a leet sploit. Rhag's room has four summoning guards. They're pretty pathetic - they can melee up to 381 or so, but don't do so often at all. Two of them don't normally aggro a level seventy right in front of rhag. They're trivial for a 70 shaman to offtank.
In everquest, the interupt check for spellcasting is done by a location delta check, not a movement check. So.. start casting a nuke. Get summoned by rhag. almost instantly get summoned by the guard. For the last little bit, I was able to basically chain cast without worrying about being interupted, even while being summoned across the room.
There were some other people inzone nearby, but they didn't touch it.
full logs are available at http://kgorman.googlepages.com/rhag.txt
Edited, Tue Apr 11 10:41:10 2006 by Groogle