Phase One
You'll get a few golems. 5 or 6 I think. They come one-by-one at timed intervals and have no special mechanics. Very easy, barely worth mentioning.
Phase Two
Brell will summon two 'visages' of himself. The Arcane one is totally immune to spells. The Armored one is immune to melee. This is a balance event (didn't you miss those?) so don't let them get too far apart hp wise. Or distance wise, because bad stuff happens if they get too far away from each other. Bad stuff also happens when they get too close (specifically, a massive pbae goes off every few seconds). Also, there's 2 detrimental auras that greatly reduce the range of beneficial spells. Yes, they both do the same thing. I can only assume one was intended to be for detrimental spells. But it is what it is. You'll need to be much closer to cast things like heals, buffs, or rezzes. In case this isn't enough, they also mem blur. Brell will shout "Time to mix things up", which means both visages just blurred. The tanks will already have enough trouble keeping aggro due to immunities, so this will get a lot of people killed. It is timed, so once you get the timing down you can anticipate a switch coming and back off. They also do an AE knockback occasionally, but that's not that bad compared to the other stuff. This is a good bit harder than Phase Three, and Emperor Crush is harder than One.
Phase Three
Brell will say he sees he can't get back to work until he deals with you directly. After a moment, Brell Serilis himself will go active. EVERYONE PILE ON TOP OF HIM. This is extremely important. He'll occasionally spawn static fields, mobs that have a large damage aura. These pop on top of random people so if everyone is piled on Brell you won't have to look far. When they pop (and they won't appear on extended target, because they don't actually attack anyone, just do AE's) everyone has to switch to them and kill them ASAP. Brell's obligatory 'follow-or-else' emote is "Yourname, I choose you" (there's nothing worse than a Pokemon reference). When you get this, run away from the raid. After the effect hits you (there's several variations) run back to the raid. When Brell gets to 20%, he'll cry uncle and you win the raid.
