MU Online Season 21 Part 3: what is new and what runs on MUOnline.ai
MUOnline.ai runs on Season 21 Part 3 server files (the label used for this private-server release; it is not a Webzen version). Webzen's own global game is on Season 21-1 Part 3 (1 September 2026); Webzen has not announced a Season 22 as of September 2026. Below is what Webzen shipped in Season 21-1, then what that means on this server.
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Webzen's Season 21-1 timeline (global)
- 21 July 2026, Part 1: the Crusader class (hammer and shield) and the Speed Server level cap raised from 800 to 900.
- 11 August 2026, 2nd update: the Sanctuary of Aquilas hunting ground (level 1,600+), the Ancestral Imperial legendary tier and the new Idavoll server.
- 1 September 2026, Part 3: the Sanctuary of Aquilas Elite Zone with double drops, plus double rewards in Maze of Dimensions, Boss Battle, Chaos Castle, Blood Castle and Devil Square.
Korea runs ahead of the global service: the Korean Season 21 updates arrived on 30 September and 28 October 2025, and Korea received a five-class renewal on 21 April 2026 and Forgotten Raklion with a level cap of 1,800 on 19 May 2026. That Korean content is not on the global service and not on this server.
What runs on MUOnline.ai
The server runs all 16 classes, including the Crusader; the full list is on the classes page. The server's own evolution names come first, Webzen's in parentheses, for example Templar Commander (Webzen: Temple Guard Commander) and Alchemist Magician (Webzen: Alchemic Magician). Whether the Sanctuary of Aquilas, the Ancestral Imperial tier or other Season 19-21 systems from Webzen's game are enabled on MUOnline.ai is being verified; each item, skill and map page shows what the server files contain.
Resets, Grand Resets, GP web currency and Vote Points are private-server mechanics exclusive to MUOnline.ai and do not exist in Webzen's game. The two realms, Permanent Realm (5000x EXP) and Speed Realm Autumn Edition (99.999x EXP), are compared on the realm page.