Experiment 12-B

Rare drop from the Lesser Cache of the Aspects, the chest that appears when Ultraxion, the fifth boss of the Dragon Soul raid, is defeated on Normal or Heroic. The raid is entered in the Caverns of Time in Tanaris; Morchok, Warlord Zon'ozz, Yor'sahj the Unsleeping and Hagara the Stormbinder come first, then a short fight against Twilight Assaulters on the Wyrmrest summit brings Ultraxion.

Chance 0.9% once a week, so about 111 tries on average — Wowhead item page (read 2026-10-11), pooled over the four Lesser Cache of the Aspects objects, which are the chest's four size and difficulty versions: 136 in 18,919 (object 210161), 174 in 32,909 (210163), 278 in 44,278 (210160) and 1,272 in 110,569 (210162), together 1,860 mounts in 206,675 recorded openings = 0.90%. Singly they run from 0.53% to 1.15%; which object is which difficulty was not looked up. The tooltip gives no figure and the wiki says only 'very rarely'

Inside Dragon Soul, a raid (Normal or Heroic, 10 or 25 player (not Raid Finder))

Time there about 20 min a visit

Nothing to unlock first: go there and take your chance.

/way is for the TomTom addon. Travel times are estimates: flying at 55 yards a second in a straight line and 30 seconds for a portal. A star marks a portal that needs a quest or other unlock done first.

One kill of Ultraxion per character each week, so more characters mean more tries (2025 comments describe running it on many alts). About 111 kills are expected at 0.90%; players on Wowhead report anything from the second kill to over 1,000. The time there is an estimate for the four bosses before him and the kill itself; it is not a full clear.

Since November 2024 only 5 Twilight Assaulters have to be killed before Ultraxion appears, down from 15 (a 2024 Wowhead comment). In the fight, by the wiki: when Ultraxion casts Hour of Twilight players step out of it with the Heroic Will button, but on 10-player Normal at least one has to stay in and take it (more on the larger and harder versions), or the raid is wiped.

Difficulty: the wiki says 'on any difficulty', but Wowhead comments of 2013 (19 votes) and 2015 say it does not drop in Raid Finder; the 2015 one adds that the in-game Adventure Guide lists it for Raid Finder all the same. Wowhead records loot for exactly four chest objects, which fits 10 and 25 player on Normal and Heroic. The guide follows the comments.

Recent drops are reported on both 10-player Normal (comments of 2023 and 2025) and 25-player Heroic (2024 and twice in 2025); nothing found shows one of them to be better. Wowhead's counts stand as recorded and take in the weeks of the Collector's Bounty event of mid-2025, when players report a raised chance for old raid mounts (2025 comments).

A second source: the Cache of Timewarped Treasures from the weekly quest Disturbance Detected: Firelands, offered only while Cataclysm Timewalking is running, can also hold it (wiki; a 2025 Wowhead comment counts 35 such caches opened without it). Wowhead counts 48 mounts in 10,585 openings of the cache (0.45%), but the wiki says a cache of the same name is given in the Black Temple and Ulduar weeks with other loot; whether Wowhead's count is for the Firelands one alone was not established.

The wiki also lists the Black Market as a place it turns up. The item binds when picked up (Wowhead's tooltip).

The entrance coordinates are from the game's own table of instance entrances, a spot inside the caverns; the cave mouth is at about 64.8, 49.9 (as given for the Twilight Harbinger). Wowhead's figures are from its retail page; its pages for older content jump to its Classic database in a browser.

Confidence in this entry: high. Looked up in 2026.

Sources

• Wowhead: experiment 12 b
• Wowhead: experiment 12 b (comments)
• Wiki: Experiment 12 B
• Wiki: Ultraxion
• Wiki: Lesser Cache of the Aspects
• Wiki: Cache of Timewarped Treasures