Rod Fergusson, Diablo general manager, kicked off his DICE Summit 2025 presentation not with a victory lap, but by addressing one of Diablo's most infamous setbacks: Error 37. This launch-day debacle for Diablo 3, caused by an overwhelming influx of players, resulted in widespread criticism and became a memorable internet meme. While Diablo 3 ultimately triumphed, the experience underscored the importance of avoiding similar catastrophes, especially given Diablo's evolution into a complex live service game with frequent updates, seasons, and expansions.
The stakes are higher than ever for Diablo 4, which has fully embraced the live service model. Another Error 37 would be devastating, jeopardizing the long-term viability Blizzard envisions for the game.
Diablo, Immortal?
At DICE Summit 2025, I spoke with Fergusson following his presentation, "Evolving Sanctuary: Building a Resilient Live-Service Game in Diablo IV." He outlined four key pillars for Diablo 4's resilience: scalable infrastructure, consistent content delivery, design flexibility, and proactive player communication. His emphasis on long-term player engagement contrasts sharply with previous Diablo titles. The commitment to a live service model signifies a shift towards sustained, evolving gameplay rather than relying on periodic numbered sequels.
I asked Fergusson about Diablo 4's longevity—is it aiming for "eternal" status like World of Warcraft, or is there a planned transition to Diablo 5? He clarified that while not aiming for eternity, the goal is sustained engagement for years to come. He emphasized respecting players' time investment by maintaining a clear roadmap and avoiding abrupt endings.
Fergusson highlighted the significant time gaps between previous Diablo releases (over a decade between Diablo 2 and 3, and another decade between 3 and 4), noting the absence of the aggressive update cadence planned for Diablo 4. He acknowledged the 18-month delay between Diablo 4's launch and its second expansion, "Vessel of Hatred," due to prioritizing live game updates and the first season. While hesitant to commit to a fixed expansion release schedule, he stressed the importance of realistic planning and avoiding premature announcements.
Ruining the Surprise…Intentionally
Fergusson's cautious approach extends to the team's increased transparency. This includes a content roadmap (to be unveiled in April) and the Public Test Realm (PTR), allowing players to test upcoming patches before wider release. He explained that the team initially hesitated to utilize a PTR or roadmap, fearing spoilers, but ultimately recognized the benefits of proactive communication.
He emphasized that a short period of potential disappointment in the PTR is preferable to a prolonged negative experience caused by unforeseen issues in a surprise release. He acknowledged that some information leaks through data mining, but the scale of the PTR's benefits outweighs the impact of a small leak.
Fergusson aims to expand PTR access to consoles, currently hindered by certification challenges. He sees Xbox's support as beneficial, especially considering Diablo 4's presence on Game Pass, which removes barriers to entry for new players and fosters consistent growth, unlike the premium model of Diablo Immortal.
All Hours Diablo
Our conversation concluded with a discussion of Fergusson's gaming habits. He revealed his top three games of 2024 by playtime: NHL 24 (third), Destiny 2 (second), and Diablo 4 (first, with over 650 hours on his personal account). He discussed his current character builds and expressed his enduring passion for the game, highlighting the routine and consistent engagement that keeps him returning.
He also addressed comparisons to Path of Exile 2, emphasizing their differences while acknowledging the need to balance player engagement across various games. His personal experience highlights the importance of understanding player behavior and preferences in designing a successful long-term live service game.
