Critical Role Announces Brennan Lee Mulligan as Campaign 4 DM

In a move that has sent ripples of excitement and speculation throughout the tabletop role-playing game community, Critical Role has officially announced that Brennan Lee Mulligan, the acclaimed Game Master of Dropout’s Dimension 20, will take the helm as Dungeon Master for the entirety of Campaign 4. The news, which was revealed ahead of a live show in Indianapolis, confirms a major shift for the popular actual play show, marking the first time in its history that a long-form campaign will not be run by co-founder Matthew Mercer.

A New Era for Critical Role and a “Breather” for Exandria

Critical Role’s fourth campaign is set to premiere on Thursday, October 2nd. This new chapter will introduce a brand-new world, completely separate from the beloved continent of Exandria. According to a press release, this decision allows for both Mercer and the world he created to take a well-deserved “breather.” While Mercer will be taking a seat at the player’s table for the first time in a full campaign, he will not be stepping away from DMing entirely. He is also reportedly working on a second miniseries for the Age of Umbra, which will use Critical Role’s new Daggerheart system.

The announcement was met with a mix of surprise and excitement from fans. As creative director and co-founder Marisha Ray stated, “We’re not just turning a page—we’re starting a whole new book.” The move signals a clear intention to create a fresh experience for both the cast and the audience, with new characters, a new setting, and the unique storytelling style of Brennan Lee Mulligan.

The Perfect Successor: A Champion of Improv and Narrative

Brennan Lee Mulligan is widely regarded as one of the most talented and creative Game Masters in the TTRPG space. His work on Dimension 20 has garnered a massive following, celebrated for its perfect blend of heartfelt character moments, high-stakes drama, and improvised comedy. He has previously collaborated with the Critical Role team on the Exandria Unlimited miniseries, which received high praise from both fans and the cast.

Mulligan expressed his own excitement on social media

Hey Gang! I could not be more thrilled to step behind the screen for Campaign 4 of Critical Role, and cannot wait to share all the amazing things me and this incredible team have been cooking up for you!

— Brennan Lee Mulligan (@brennanleemulligan.bsky.social) August 2, 2025 at 7:43 PM

His ability to weave intricate plots while reacting to player choices in real-time makes him an ideal choice to continue the tradition of collaborative storytelling that defines Critical Role. While details on the cast and game system for Campaign 4 are still under wraps, the choice of Mulligan as DM promises a campaign that will be both epic and unforgettable.