Entrance
Underground night elf barrow network; entrances incl. Mount Hyjal and Blackmaw Hold tunnels (Azshara) - 'one of three entrances'
Loot and attunement
Attunement TBD. New tier sets and a legendary reward tied to the Dec 9 raids. Legacy Challenge 'Conqueror of the Deeps'. No flex sizing; fixed tuning (Ana Resendez). Chase items on every boss (Zierhut/Nuthals).
Description
'A maximum-level 10-player challenge.' Night elves' prison for their most dangerous captives (includes an infamous demon hunter's cell - Illidan implied) and barrows where Druids of the Claw sleep; corruption theme. Connected to a legendary reward 'we're looking forward to revealing in full'.
Forever evidence
confirmed_official (10-player, max level, legendary tie); release date confirmed_panel; boss names reported_demo (from Legacy Challenge listings in BlizzCon demo, per Blizzard Watch)