At the DICE Summit 2025, Rod Fergusson, the general manager of the Diablo series, opened his talk with a candid reflection on one of the franchise's most notable setbacks: Error 37. This infamous error struck at the launch of Diablo 3, preventing countless players from accessing the game due to server overload. The incident led to widespread criticism and even became a meme within the gaming community. Blizzard eventually resolved the issue, and Diablo 3 went on to achieve success, but the experience left a lasting impression on Fergusson and the team. With Diablo 4 evolving into a more intricate live service game, complete with regular updates, seasons, and expansions, avoiding a repeat of Error 37 is crucial for maintaining the game's longevity and player satisfaction.

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, embracing flexibility in design, and keeping players informed about future updates.

Fergusson emphasized the importance of keeping players engaged over the long term, contrasting the approach with previous Diablo titles. The commitment to a live service model reflects a broader trend in the gaming industry, where major titles are designed to evolve continuously rather than relying on new releases every few years.

When asked about the future of Diablo 4, Fergusson hinted at a long-term vision for the game. "We want it to be around for years," he stated, acknowledging the challenges of committing to an eternal game while also respecting players' time and investment. He referenced the long gaps between previous Diablo releases, but highlighted the unique approach Diablo 4 is taking under his leadership since joining Blizzard in 2020.

Fergusson also discussed the delay of Diablo 4's second expansion, Vessel of Hatred, to 2026. Initially planned for annual releases, the timeline shifted as resources were redirected to support the live game and its first season. Fergusson expressed caution about setting firm timelines for future expansions, learning from past experiences not to promise too much too soon.

Ruining the Surprise...on Purpose

Transparency is another key aspect of Fergusson's strategy for Diablo 4. He discussed the use of content roadmaps and the Public Test Realm (PTR), where players can test upcoming patches before they go live. Initially hesitant about spoiling surprises, Fergusson now believes that transparency benefits the majority of players. "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 during his talk.

Fergusson also shared plans to extend the PTR to console players, currently limited to PC due to certification challenges. With the support of parent company Xbox, Blizzard is working to overcome these obstacles. Additionally, the availability of Diablo 4 on Game Pass helps attract more players, reducing entry barriers and fostering a growing community.

All Hours Diablo

In our conversation, I asked Fergusson about his current gaming habits and whether he had played Path of Exile 2, a game often compared to Diablo 4. He dismissed the comparison, noting that the games are fundamentally different, but acknowledged the need to consider players who enjoy both titles. He mentioned feedback from players requesting non-overlapping seasons to allow them to enjoy both games without having to choose between them.

Fergusson's top three games of 2024 by playtime are NHL 24, Destiny 2, and, unsurprisingly, Diablo 4. With over 650 hours logged on his personal account, he continues to play Diablo 4 extensively, currently favoring the Companion Druid and Dance of Knives Rogue classes. His passion for the game, which brought him to Blizzard five years ago, remains undiminished, even as he balances work and play.