A Warlock's Overview: Please feel free to add information.
o Very similar to the end boss in SV. He channels. Kill the crystal before he finishes. When he channels the crystal, he gets mana from it. When he has mana, he uses fel explosion (AoE) until he's out of mana. Thus, the less mana he has, the better off you are. He does a drain life spell that is rather nasty, should be dispelled (paladin only?) or interrupted.
o Overall? Piece of Cake.
o Similar (sort of) to Curator. He summons little flares that need to be downed. The killer of the flare gets a DoT that can stack up to 30 times. At about 15-20%, Vex enrages and needs to be burned down fast. Apparently, this is a fight that depends on the healer's ability to keep people alive, more so than a DPS fight. I disagree. Kill Vexallus really fast, and you don't have too many of those flares to deal with, do you? Reports in WoWWiki are mixed, one says flares appear with health (in which case, doesn't matter how fast or slow you kill him), another says it's time based, in which case the faster the better.
o Overall? Piece of Cake.
o Similar (sort of) to Moroes. You get a random assortment of four additional mobs with the Priestess. Though she looks like a demon, she's listed as humanoid.
o NONE OF HER ADDS ARE SEDUCABLE. This really burns me. It really does. Sheeping and hunter trapping work, but seducing doesn't. So, if you have a group of warlocks, this sucks for you.
o The demons ARE banishable. Stack a CoS on it to make the banish last longer.
o The adds are fearable. Clear the room before Delrissa's completely if you use this method, and try to keep the feared mobs back there.
o Priestess can be hunter trapped. However, we did best when we killed her first.
o Warlock's imp (Fizzle) is one-two shottable, but he'll resummon, so keep an eye out for it.
o Hunter's pet (Sliver) has a fast attack, it needs to be kept off of the healer so he can heal.
o Shadow Word: Pain could/should be left on the dispeller (if only one person can dispel it), to wake them up from any CC effects that may happen to them.
o To my knowledge, her adds can be sheeped, hunter trapped and possibly sapped. Seduce won't work. NOT TAUNTABLE!!
Priestess' Group Members
* Apoko: Shaman. Will purge effects off of people, including Righteous Fury and Holy Shield.
* Brightblaze: Fury Warrior. Kicks and stuns.
* Duskhallow: Warlock. Fears and SoC's.
* Garaxxas: Demon Hunter. Freezing trap on group and warstomp (stun)
* Nightstrike: Rogue: Cheap Shot, Kidney Shot and Gouge (stuns), vanishes and poison (crippling).
* Salaris: Warrior. Intimidating Shout is the biggest concern group wise, also mortal strike and charge abilities.
* Yazzai: Mage: Polymorph is the biggest concern, all the rest are ice-mage abilities (ie: blizzard, frost nova, etc)
* Zelfan: Engineer: AoE Sheep and frontal flame arc.
o Strategy: Tanks are very little use in this fight to some extent, since they are not tauntable. The tank should hold mobs on them as much as possible, but once the DPS really gets going, it may be hard to hold onto the target. Have a well established kill order, so the healer isn't healing too many DPS at once.
o The priestess does negligible melee damage, killing her first is ususally suggested.
o Keeping the intimidating shout warlord CC'd until last is the best, otherwise OUR CC breaks while we're running. Hard to fear something when you're running in fear yourself.
o Priestess's healing spells have no cooldown. She can spam heal herself and others. Keep her controlled or silenced/kicked.
o Overall: VERY GROUP DEPENDENT, not just your group, but what her group consists of. We had a hard time with it as we had two warlocks in the group and only one demon, so our CC was limited.
o Overall, almost anticlimatic. The group pull before him was harder than he was.
o Phoenix: Have someone kite it away from the group until it dies. Once it dies, all DPS need to kill the egg. If you do not kill the egg, the phoenix is reborn stronger. We used a warlock to do this, since DPS could be maintained on both Kael'thas and the phoenix.
o Kael'thas does summon more than one phoenix in the fight. Be ready.
o Flamestrike shows up as three glowy balls swirling around one another. Initial damage is quite severe, so move out of it.
o At 50%, the tank becomes nothing more than an ornament. This is when Gravity Lapse theorhetically starts. (I wasn't watching his % of life)
o Gravity Lapse was really very fun! Though it's "swimming", it's very FAST swimming, so don't overdo it. Avoid the floor and avoid the water balls, and just keep DPSing him. Try to keep health up at this time as during Gravity Lapse, you're taking constant damage from Kael'thas.
o Begin Gravity Lapse by the door out, so the water-balls have to come all the way to you. Then ZIP past them to by Kael'thas and keep DPSing him there, making them have to return to you from across the room.
o In between Gravity Lapses, just DPS to the max on Kael'thas. He doesn't do melee damage, just recovers then does Gravity Lapse again.
o Overall: Anticlimatic.