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 lasting meme. While Diablo 3 eventually triumphed, the experience underscored the importance of preventing similar catastrophes, especially with Diablo's evolution into a complex live-service game featuring frequent updates, seasons, and expansions.
The stakes are higher than ever for Diablo 4, a title fully embracing the live-service model. Another Error 37 would be devastating, jeopardizing Blizzard's ambition for Diablo 4 to become a long-lasting live-service juggernaut.
Diablo, Immortal
At DICE Summit 2025 in Las Vegas, I spoke with Fergusson following his presentation, "Evolving Sanctuary: Building a Resilient Live-Service Game in Diablo IV." He highlighted four key pillars for Diablo 4's resilience: scalable infrastructure, consistent content delivery, design flexibility, and proactive player communication. Fergusson emphasized the commitment to long-term player engagement, a significant departure from previous numbered Diablo titles. The planned content roadmaps and extensive season planning represent a shift towards a sustained live-service model, unlike the traditional approach of releasing new numbered installments every few years.
This led to the question: Is Diablo 4 destined for immortality, or is there a point where Blizzard will move on to Diablo 5? Fergusson's answer: "We want it to be around for years," he stated. He acknowledged the ambitious nature of a long-term live service game, referencing Destiny's "ten-year game" pledge, which ultimately fell short. Fergusson emphasized the importance of respecting players' time investment by providing a clear roadmap and ensuring sustained engagement.
He pointed out the lengthy gaps between Diablo 2 and 3, and then 3 and 4, highlighting that those games lacked Diablo 4's aggressive update cadence. However, he also admitted to learning from past experiences: Fergusson announced at the summit that Diablo 4's second expansion, Vessel of Hatred, was delayed until 2026, extending the original timeline due to shifting resources to address immediate live-game updates and the first season's launch. This resulted in an 18-month gap between Diablo 4's release and Vessel of Hatred, rather than the planned 12. When pressed on whether this 18-month timeframe would become the new standard, Fergusson remained cautious, stating, "I learned my lesson about calling the shot too early."
Ruining the Surprise…on Purpose
Fergusson's caution is understandable, particularly given the team's commitment to unprecedented transparency. This includes the upcoming content roadmap (revealed in April) and the Public Test Realm (PTR), allowing players to test upcoming patches before official release. Initially, the team hesitated to utilize features like the PTR or roadmaps, fearing spoilers. However, Fergusson has changed his perspective:
"You just realize that it's better to ruin the surprise for 10,000 people so that millions of people have a great season," he explained. He emphasized that a short period of potential PTR issues is preferable to the fallout from releasing a flawed, surprising update.
Fergusson aims to expand PTR access to consoles, currently limited to PC due to certification hurdles. He notes that Xbox's support is aiding these efforts. He also highlighted the positive impact of Diablo 4's inclusion in Game Pass, removing barriers to entry and attracting a steady stream of new players.
All Hours Diablo
Our conversation concluded with a discussion of Fergusson's personal gaming habits. He revealed his top three games of 2024 by playtime: NHL 24 (third), Destiny 2 (second), and, unsurprisingly, Diablo 4 (first), with over 650 hours logged on his personal account alone. He explained his dedication to the game, stating, "It's something about the habit of the game." His passion for Diablo, both personally and professionally, is evident.
