At the DICE Summit 2025, Rod Fergusson, the general manager of the Diablo series, kicked off his talk with a candid discussion about one of the franchise's most notorious setbacks: Error 37. This error, which plagued the launch of Diablo 3, left countless players unable to access the game due to an overwhelming influx of simultaneous logins. The resulting backlash against Blizzard's launch management was intense, with the error even becoming a meme. Although Blizzard eventually resolved the issue and Diablo 3 went on to achieve success, the experience left a lasting mark on the team. Fergusson emphasized the importance of learning from such failures to prevent similar incidents, especially as Diablo evolves into a more intricate live service model with frequent updates, ongoing seasons, and planned expansions. The stakes are even higher for Diablo 4, which has fully embraced this live service approach, making it crucial to avoid another debacle like Error 37 to ensure the game's longevity.

Diablo, Immortal

During the DICE Summit 2025 in Las Vegas, I had the opportunity to speak with Rod Fergusson after his presentation titled “Evolving Sanctuary: Building a Resilient Live-Service Game in Diablo IV.” In his talk, Fergusson outlined four key strategies for ensuring the resilience of Diablo 4: scaling the game effectively, maintaining a steady flow of content, being flexible with design purity, and keeping players informed about future updates without spoiling the surprise. He stressed the importance of retaining players over the long term through consistent engagement and a clear content roadmap, a significant shift from the traditional model of numbered releases every few years.

When asked about the future of Diablo 4, Fergusson hinted at a long-term vision but stopped short of declaring it "eternal." He compared it to other live service games, noting that while Destiny aimed for a decade-long commitment and didn't quite achieve it, Diablo 4 aims to respect players' time by providing a clear road ahead. Fergusson pointed out the lengthy gaps between previous Diablo releases, but emphasized that Diablo 4's aggressive update schedule sets it apart. He joined Blizzard in 2020 after leading the Gears franchise and brings a forward-thinking yet cautious approach to Diablo's development.

Fergusson shared that the second expansion for Diablo 4, originally slated for annual releases, will not arrive until 2026 due to shifts in development priorities. He learned from past experiences not to set rigid timelines too early. "I learned my lesson about calling the shot too early," he said, indicating a more flexible approach to future announcements. This cautious stance extends to the game's content roadmap and public test realms (PTRs), where players can preview upcoming patches.

Ruining the Surprise...on Purpose

Fergusson's team is committed to transparency, even if it means spoiling some surprises. The content roadmap, set to be revealed in April, and the PTR are part of this strategy. Initially, there was reluctance to use these tools due to concerns about spoiling surprises, but Fergusson believes that it's better to "ruin the surprise for 10,000 people so that millions of people have a great season." He acknowledges that while data mining and leaks can occur, the impact is minimal compared to the overall player base.

Expanding the PTR to consoles is another goal, though currently limited to PC due to certification challenges. With the support of parent company Xbox, Blizzard is working to overcome these obstacles. Fergusson also highlighted the benefits of Diablo 4's inclusion on Game Pass, which removes barriers to entry and attracts a steady stream of new players, contrasting with the model of Diablo Immortal, a free-to-play live service game.

All Hours Diablo

In our final discussion, I asked Fergusson about his recent gaming habits, hoping to understand his inspirations. He dismissed comparisons between Diablo 4 and Path of Exile 2, stating, "They’re very different games." However, he aims to cater to fans of both by ensuring that the seasons of each game do not overlap, allowing players to enjoy both without having to choose.

Fergusson's top three played games of 2024 are NHL 24, Destiny 2, and, unsurprisingly, Diablo 4. He has logged 650 hours on Diablo 4 on his personal account alone, not including work time. Currently, he's playing as a Companion Druid and a Dance of Knives Rogue, showcasing his deep love for the game. He describes his gaming habits as driven by routine, often returning to Diablo 4 despite being halfway through other games like Cyberpunk and The Witcher 3. His dedication to Diablo, both professionally and personally, remains unwavering.