Dimension 20

Dimension 20 is Brennan Lee Mulligan's anthology actual play series, and it might have the highest production values in the entire genre. Originally a video show on Dropout (formerly CollegeHumor's streaming service), the podcast version brings the audio from these meticulously crafted campaigns to your earbuds. The first season, Fantasy High, is a love letter to both D&D and teen coming-of-age movies, set in a world where adventuring is the high school curriculum. Mulligan's DMing style is electric. He builds worlds with an almost manic creative energy, voices dozens of distinct NPCs, and adapts to his players' chaotic choices with the kind of improv skill you would expect from someone with a background in competitive storytelling. The cast rotates between seasons, drawing from a roster of comedians and performers. You will see names like Emily Axford, Zac Oyama, Ally Beardsley, and Lou Wilson across different campaigns, each bringing wildly different energy. The podcast feed on Apple has about 41 episodes from the earlier seasons, but the full Dimension 20 library lives on Dropout with dozens of complete campaigns spanning fantasy, noir, sci-fi, and even a Willy Wonka parody. In 2025, Mulligan signed a three-year deal with Dropout and also took over as GM for Critical Role's fourth campaign, cementing his status as arguably the most in-demand game master working today. The Fantasy High Webtoon adaptation launched in March 2025, and the Battle at the Bowl live event at the Hollywood Bowl was a massive spectacle.