Diablo general manager Rod Fergusson opened his DICE Summit 2025 talk not by discussing success, but by revisiting one of Diablo's most infamous failures: Error 37.
Error 37 was a server capacity error that plagued the launch of Diablo 3, blocking player access due to the overwhelming number of simultaneous login attempts. This widespread issue drew significant criticism towards Blizzard's launch management and even became an internet meme. While Blizzard eventually resolved the error and Diablo 3 became a long-term success, the memory of that rocky start lingers.
Naturally, Blizzard and Fergusson are determined to prevent a repeat, especially as Diablo evolves into a more complex live service model. With frequent updates, seasonal content, and major expansions planned at regular intervals, Diablo 4 has embraced the live service approach more fully than any of its predecessors.
Another incident like Error 37 would be catastrophic, particularly if Blizzard aims for Diablo 4 to thrive well beyond its major content drops as a true live service powerhouse.
Diablo, Immortal
Following his DICE Summit talk titled "Evolving Sanctuary: Building a Resilient Live-Service Game in Diablo IV," series general manager Rod Fergusson discussed the franchise's future. On stage, he outlined four pillars for Diablo 4's resilience: scalable infrastructure, consistent content delivery, pragmatic design evolution, and transparent player communication—even if it means fewer surprises.
A central theme was fostering long-term, consistent player engagement. The detailed content roadmaps and season planning represent a significant shift from previous numbered Diablo titles. While expansions are not new to the series, Diablo 4 is committing to a modern live service model, aiming for longer lifespan and more frequent evolution rather than relying on a new numbered sequel every few years.
This raises a key question: is Diablo 4 intended to be eternal—or perhaps *immortal*? Is there a benchmark for when development shifts to Diablo 5, or could Diablo 4 become *the* definitive Diablo experience indefinitely, similar to World of Warcraft?
Fergusson's response: perhaps not forever, but certainly for a very long time if he has any say. "We want it to be around for years," he stated. "I think Destiny tried to position itself as a ten-year journey and then had to backtrack. We want players to see a clear road ahead. When you invest hundreds of hours into a Diablo game, you deserve to know we respect that commitment and are here for the long haul."
He notes the decade-long gaps between Diablo 2, 3, and 4, acknowledging that those earlier games did not have the aggressive update schedule planned for Diablo 4. Now at the helm since 2020, Fergusson believes in planning ahead—but with restraint. "I learned my lesson about calling the shot too early," he admits.
This lesson is evident in the timeline for Diablo 4's second expansion, now slated for 2026 instead of the originally planned annual release. Delays occurred as teams were redirected to address post-launch and Season 1 needs. When asked if an 18-month expansion cycle is now standard, Fergusson declined to commit. "We're not at a place where we want to put a stake in the ground. We're still building, learning, and reaching internal certainty before making public announcements."
Ruining the Surprise…on Purpose
This caution aligns with a new philosophy of transparency. An upcoming content roadmap in April and an expanded Public Test Realm (PTR) are key tools. Initially, the team worried about spoiling surprises for players but has since prioritized stability over secrecy.
"It's better to ruin the surprise for 10,000 PTR players so that millions have a great season," Fergusson explained. "I'd rather have a bad PTR week than spend three months recovering from a flawed surprise update."
He elaborated further: "We used to get anxious about data mining. But if a spoiler reaches 8,000 people on a Reddit thread, we haven't ruined the surprise for millions of future players."
A current challenge is expanding PTR access to console players, currently limited to PC via Battle.net due to certification hurdles. With Xbox's support, Blizzard is investing in solutions.
Game Pass is another strategic advantage, lowering the entry barrier. Fergusson compares it to launching on Steam: it's about maximum reach. "Unlike free-to-play games, a premium game like Diablo 4 has an entry barrier. Game Pass removes that, allowing new players to discover it constantly, which is crucial for sustaining a live service."
All Hours Diablo
Wrapping up, Fergusson shared his recent gaming habits. When asked about Path of Exile 2 comparisons, he sees them as very different games but is mindful of player time. "Many fans ask us not to overlap our seasons with competitors', so they can enjoy both. As a multi-game player myself, I completely understand that."
So what tops his playtime list? His 2024 top three: third place, NHL 24; second, Destiny 2.
First place, unsurprisingly, is Diablo 4. With 650 hours on his personal account (excluding work time), he's currently playing a Companion Druid and a Dance of Knives Rogue. His passion is evident. "There's a habitual nature to it," he said. "I get interrupted from story-driven games, but I maintain my daily routines in NHL or Destiny with my brother. I came to Diablo five years ago because it was my favorite game to play. Working on it doesn't stop me from going home and playing it for hours more."
