What Critical Role’s New DM Can Learn from Dimension 20

Critical Role’s fourth campaign has already upended expectations, not least due to its sprawling 13-member ensemble, who have promptly split into three distinct parties, each weaving their own threads through a shared tapestry. The most striking shift, however, is the arrival of Brennan Lee Mulligan as the new Dungeon Master, stepping into the shoes of the long-serving Matthew Mercer. Mulligan, celebrated for his stewardship of Dimension 20, brings a markedly different sensibility to the table. While the scale of this campaign dwarfs his previous projects, his influence is unmistakable. His background in comedy, penchant for genre play, and readiness to adapt the rules are already reshaping the experience, and this is only the beginning.

As someone who’s spent countless hours immersed in actual play series, I first encountered the format through Critical Role’s second campaign. After finishing that, I retraced my steps to the first and then sampled the third. Only after this did I venture into Dimension 20, quickly finding myself captivated. Where Critical Role offered deep character studies and slow-burning romance, Dimension 20 delivered something brisk, clever, and genuinely funny. Returning to Critical Role for this new chapter, I’m reminded of the depth that long-form campaigns can offer, but I’m also hoping the show will embrace some of Mulligan’s innovations—even if it means shaking things up considerably.

Multiple Narratives and Shared Spotlight

In a conversation before the launch of campaign four, Mercer observed that juggling several storylines allows for a

"much more realistic way"

of exploring fantasy. The rotating cast of thirteen does more than complicate the seating arrangement; it fundamentally alters the narrative structure. Earlier campaigns often saw individual characters carrying the weight of long-running arcs, with Mercer striving for balance but inevitably some players taking centre stage. Dimension 20, by contrast, distributes attention more evenly. Even when one player’s story comes to the fore, Mulligan ensures everyone remains involved, never letting any one arc dominate proceedings.

Stripping away the production gloss and professional acting, Dungeons & Dragons is, at its core, a game of rules. Mercer has always adhered closely to these, which, for me, made the third campaign feel a touch too safe. The stakes were high, but the sense of risk was muted—resurrection spells and plot armour dulled the edge. Dimension 20, meanwhile, hops between genres and settings, with Mulligan tailoring the rules to fit the tone. Sometimes the story offers a lifeline; at other times, it’s ruthlessly unforgiving.

Redefining Peril and Pacing

The opening act of campaign four wastes no time in establishing its new rules. A character’s death occurs, yet no one so much as mentions the resurrection spell Revivify. The premise is that the gods are gone, and in this world, it’s divine power that governs life and death. Mulligan sets out his stall early: the rules have changed, and so has the atmosphere. Danger is immediate, not theoretical. While the precise mechanics of death and revival remain under wraps, the cast have hinted at preparing backup characters. There’s a suggestion that death may not be the end, but the boundaries are clearly different this time.

For those tempted to try their hand at a tabletop adventure, the latest D&D starter set is arguably the best yet. In Mercer’s campaigns, entire sessions might be devoted to romantic evenings, magical home tours, or shopping for finery. Some players relish this level of detail, and Mercer is committed to ensuring everyone enjoys themselves. Mulligan’s games, on the other hand, are driven by genre rather than character minutiae. Money is only relevant if it serves the story; backstories emerge through action, not lengthy chats; relationships are established with brisk efficiency. His comedic background has honed his sense of timing, and the shorter format of Dimension 20 leaves little room for dawdling.

Blending Styles for a New Era

The extended runtime of campaign four will allow for richer character exploration, but with so many players, maintaining momentum will be vital. This is already evident, and as the episodes mount, the need for deft pacing will only grow. Both Mercer and Mulligan are masterful Dungeon Masters, each with their own approach to storytelling and world-building. Rather than fostering rivalry, Mercer’s decision to bring Mulligan on board signals a willingness to evolve. In time, we’ll see just how this collaboration shapes the campaign. Perhaps, in the not-too-distant future, we’ll even see Mercer helm a short, genre-driven series in the Dimension 20 mould.