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Blizzard's mobile ARPG Diablo Immortal will soon cross over with World of Warcraft, with the most iconic weapon from the MMORPG up for grabs as part of a limited-time event.

As detailed in a blog post, Frostmourne, the legendary weapon of Arthas, the Lich King, will soon arrive in Sanctuary. Unfortunately, the arrival of the Lich King's weapon is also accompanied by portals filled with undead, which players will need to battle against over the course of the July 4-26 event. They'll receive a little undead help of their own, however. A new power, Chill of the Frozen Throne, will see players earn a 10% damage increase after killing five monsters, as well as the ability to raise up to five skeletal minions to fight by their side, no Necromancer required.

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There are a few special cosmetic rewards for the event. Simply logging in will earn players a Icecrown portrait frame, while seeing the event to its completion will unlock the Frostmourne weapon cosmetic, allowing players to wield the Lich King's weapon as their own. Making any purchase in Diablo Immortal over the course of the event will earn players a town portal skin: one inspired by the Lich King's fortress of Icecrown Citadel.

News of Frostmourne appearing in Diablo Immortal comes shortly after dataminers discovered the appearance of Frostmourne in the Season 5 public test realm build of Diablo 4, leading fans to believe a WoW crossover is in store for it as well. Blizzard hasn't made any official announcements, but given this year will be WoW's 20th anniversary, it certainly would make sense for Blizzard to offer crossover events across its various games. It would hardly be the first time WoW and Diablo have bled into one another, as there are wieldable Warcraft weapons in Diablo 3 and, last year, WoW held an in-game Treasure Goblin event complete with various Diablo-themed cosmetics to celebrate the launch of Diablo 4.

Diablo Immortal is building towards the return of Diablo himself to the free-to-play mobile game later this year, according to Blizzard's 2024 content roadmap. It more recently released a new class, the water-bending Tempest, joining the Blood Knight as the game's second never-before-seen class for the franchise.

As for Diablo 4, its most-recent Loot Reborn update has gone over well with many in the game's community. The upcoming Diablo 4 Season 5 will introduce a new roguelite-inspired endgame mode ahead of the release of the game's first expansion, Vessel of Hatred, on October 6.

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