First boss in The Voidspire, Imperator Averzian has one phase of mechanics that repeats until defeated. The boss summons sets of three adds that are immune to damage until hit by Umbral Collapse, a large group soak. Once two of the three adds are defeated, the third add leaves behind a portal. The goal of the fight is to prevent three adjacent portals from empowering each other, which allows the boss to cast March of the Endless, wiping the raid.
Tank in the middle zone.
Bloodlust on pull.
Don't let three in a row get claimed.
Three adds spawn, that attempt to claim their section.
Remove one add by stacking the tank soak on them. Several raiders also stack on soak.
Second tank taunts, gets another tank soak, place over another add.
Kill remaining large add and any smaller adds, away from the boss and other portals.
Small adds come from portals. Kill.
Dodge swirlies, spikes, etc.
Keep boss away from adds and portal zones (gains a buff when close)
Heroic:
Small adds will try to get back to a portal to heal - stop them!
Desolation - blue soak circle on one of the claimed zones - one player soaks.