Diablo 4's anniversary season launches hours late after login errors

Diablo 4's 30th-anniversary season went live more than six hours late after login errors locked players out on launch day. Season of Hell's Legacy, also called Season 15, had been scheduled to start rolling out on 15 September at 9:30 a.m. PT, according to Blizzard Blizzard.

Then the errors hit. Players trying to log in reported codes 300006 and 300008. The official Diablo account said on 15 September it was aware of an issue preventing some players from reaching the game and that the team was investigating.

A follow-up message said the season start was held back because of continuing issues Eurogamer. Blizzard later confirmed the login problems were resolved, but some game features had to be temporarily disabled to keep the game stable. The details were set out in a "PSA - Login Delay & Issues" notice published on 15 September on the official Diablo 4 forums and on the Diablo X account Blizzard Forums.

For anyone new to it, a season in Diablo 4 is a timed chapter with a fresh quest and new gear that runs alongside the main game. This one celebrates 30 years of Diablo, the dark fantasy action series centred on the war between heaven and hell. It was billed as the big anniversary season, and it brings back Deckard Cain, the scholar who has guided players since the early games.

Cain leads a quest that pits players against Baal, Mephisto and Diablo, the demons at the heart of the series. The season also adds nine Legacy Unique items, named top-tier weapons and armour inspired by classic pieces from Diablo's past. Blizzard had tested those updates early on the 3.2.0 PTR, a separate test server where players try features before release, which it said was intended to test updates and features ahead of the next season.

The launch coincided with another first: the arrival of Diablo 4 on Switch 2. The season itself was unveiled at BlizzCon 2026, Blizzard's own fan convention, with the plans recapped by the studio on 12 September. That event also set out what comes next.

Blizzard said the Amazon, the spear-and-javelin fighter from Diablo 2, will return to Diablo 4 in a paid pack in the first half of 2027. It also surprise-announced Diablo 5 for release in 2029, alongside an animated Diablo show for Netflix.

For players, this means a slow start rather than a lost launch. The anniversary quest and loot are now live, even if some features remain switched off while the fix is completed. What makes this stand out is the timing: a season meant as a celebration opened with a wait, then a staggered return.