At the DICE Summit 2025, Rod Fergusson, the general manager of the Diablo series, opened his discussion not with tales of triumph, but by revisiting one of Diablo's most notorious setbacks: Error 37. This infamous error plagued the launch of Diablo 3, blocking countless players from diving into the game due to server overload. The backlash was significant, spawning memes and putting Blizzard under the microscope. Although Blizzard eventually resolved the issue and Diablo 3 went on to be a success, the experience left a lasting impression on Fergusson and Blizzard, spurring a commitment to prevent similar issues in the future, especially as Diablo evolves into a more intricate live service model with regular updates, seasons, and expansions. Diablo 4, in particular, has fully embraced this live service approach, making the stakes even higher to avoid a repeat of Error 37, which could be devastating to its long-term viability as a live service juggernaut.

Diablo, Immortal

During the DICE Summit 2025 in Las Vegas, I had the chance to speak with Rod Fergusson following his keynote speech titled "Evolving Sanctuary: Building a Resilient Live-Service Game in Diablo IV." In his presentation, Fergusson outlined four critical pillars for ensuring the resilience of Diablo 4: scaling the game effectively, maintaining a steady flow of content, embracing design flexibility, and keeping players informed about future updates even if it means sacrificing some element of surprise.

Fergusson emphasized the importance of keeping players engaged over the long term, contrasting the approach with previous Diablo games. The series has historically relied on expansions and updates, but Diablo 4 is set to follow the live service model, which is becoming increasingly prevalent among major AAA titles, allowing games to evolve and remain relevant well beyond their initial release.

When asked about the longevity of Diablo 4, Fergusson expressed a desire for the game to remain active for many years, though he stopped short of declaring it eternal. He drew parallels with other live service games like Destiny, which promised a decade-long lifespan but adjusted its plans. Fergusson's vision for Diablo 4 is to provide players with a clear roadmap, acknowledging the significant time investment players make and ensuring that the game respects that commitment.

Fergusson highlighted the significant gap between the releases of Diablo 2 and 3, and then 3 and 4, but noted that neither of those games had the frequent update schedule that Diablo 4 aims to maintain. Since joining Blizzard in 2020 after years with the Gears franchise, Fergusson has brought a forward-looking perspective to the series, albeit with caution against overcommitting to timelines. He cited the example of Diablo 4's second expansion, Vessel of Hatred, which was delayed from a planned annual release to 18 months after the game's launch. Fergusson is cautious about setting rigid schedules, preferring to ensure internal certainty before making public commitments.

Ruining the Surprise…on Purpose

Fergusson's approach to transparency is a key element of Diablo 4's strategy. The upcoming content roadmap, set to be revealed in April, and the Public Test Realm (PTR) are tools to keep players informed and involved. Initially, the team grappled with the idea of spoiling surprises, but Fergusson believes it's better to "ruin the surprise for 10,000 people so that millions of people have a great season." He acknowledges that even if a PTR session goes awry, it's preferable to a months-long recovery from an unexpected issue in the live game.

Expanding the PTR to console players is a challenge Fergusson is keen to tackle, hindered currently by certification processes and the complexities of console updates. However, with the support of parent company Xbox, Blizzard is working to overcome these hurdles. Fergusson also praised the benefits of having Diablo 4 on Xbox Game Pass, which removes barriers to entry and allows for continuous influx of new players, contrasting it with the model of Diablo Immortal, a free-to-play live service game.

All Hours Diablo

In our conversation, I inquired about Fergusson's gaming habits to understand his influences. He dismissed comparisons between Diablo 4 and Path of Exile 2, noting their distinct differences, but acknowledged the need to consider fans of both games in future updates. He mentioned that many players prefer not to have overlapping seasons, allowing them to enjoy each game without conflict.

Fergusson shared his top three games of 2024 by playtime: NHL 24 in third, Destiny 2 in second, and unsurprisingly, Diablo 4 in first. With 650 hours on his personal account alone, Fergusson's passion for Diablo is evident. He's currently playing as a Companion Druid and has recently started a Dance of Knives Rogue, illustrating his deep engagement with the game. His love for Diablo, both professionally and personally, drives his vision for the franchise's future.