What the achievement asks
Kill both bosses of Crucible of Storms: The Restless Cabal and Uu'nat, Harbinger of the Void. Ten points, account-wide, both factions.
Crucible of Storms is the smallest raid in Battle for Azeroth. Two encounters, no branching, no gating beyond killing the first before the second. For a meta hunter it is the cheapest raid on the list.
The two encounters
The Restless Cabal is a single criterion but two bodies: Zaxasj the Speaker and Fa'thuul the Feared are fought together and share the encounter.
Uu'nat, Harbinger of the Void follows immediately after. He was the hardest fight in the game when the raid was current, which matters not at all now: at modern levels the raid falls over.
Difficulty
Crucible of Storms names no difficulty at all, at either the encounter level or the raid level. Any difficulty earns it, Raid Finder included.
The raid sits under the Shrine of the Storm in Stormsong Valley, and it is easy to overlook precisely because it is so small. If you are working through Battle for Azeroth raids for the meta, this is the one to do first: two pulls and it is closed.
The other raids in this meta
Crucible of Storms is one of five Battle for Azeroth raids the meta asks for, and by a wide margin the shortest:
- Uldir, eight bosses, Normal or higher
- Battle of Dazar'alor, nine encounters in three wings, Normal or higher
- Crucible of Storms, two bosses, any difficulty
- The Eternal Palace, eight bosses, any difficulty
- Ny'alotha, the Waking City, twelve bosses, Normal or higher