New Spell Unveiled in Critical Role Campaign 4 by Ex-Dungeons and Dragons Lead Designer

If there’s one thing fans of Critters should be aware of, it’s that the Critical Role cast loves to sprinkle homebrew elements into their Dungeons & Dragons adventures. Homebrew refers to the custom content—like rules, items, or settings—crafted by players or the Dungeon Master, which isn’t found in official Wizards of the Coast materials. Campaign 4 continues this tradition, introducing a fresh spell during the latest episode of Critical Role’s post-game discussion show, Cooldown.

After an action-packed episode, the Schemers table took a moment to chat about their level-ups. While many players at the table are spellcasters, it was Marisha Ray, who plays the charismatic bursar of Dol-Makjar’s magical school, the Penteveral, who teased fans with the spells she selected upon reaching 4th level as a wizard.

“I had good old Chris Perkins help me cook something up; it’s a spell called Magical Bug, which is exactly what it sounds like,” Ray shared with her fellow cast members. She was referring to Christopher Perkins, the former creative director of Dungeons & Dragons, who recently transitioned to Darrington Press alongside game director Jeremy Crawford.

Ray explained that the spell takes a minute to cast and allows a character to inscribe an invisible rune on an object, enabling her to eavesdrop on conversations within a 30-foot radius of the bug.

While it may not shine in combat scenarios, it’s particularly useful for the Schemers. Unlike other groups, the Schemers are deeply involved in the daily life of Dol-Makjar. Azune Nayar (Luis Carazo) serves as an Arcane Marshal in the Revolutionary Guard, while Halandil Fang (Liam O’Brien) is a prominent figure who owns and runs a theater. Murray (Ray) is the bursar of the Penteveral, and Bolaire Lathalia (Taliesin Jaffe) curates the Archanade museum. Their roles put them in contact with the elite of the Sundered Houses, making them vulnerable if their schemes are uncovered.

With Magical Bug, Murray has the potential to plant the rune in a location where she might overhear discussions that could benefit not just the Schemers but also the other groups. However, this spell comes with its own risks, as many of the Sundered Houses are skilled in magic, meaning the rune could be detected despite its invisibility—especially if someone casts Detect Magic.

This isn’t the first instance of homebrew content in Campaign 4. Matthew Mercer’s fighter/rogue Sir Julien Davinos features a custom subclass called Daredevil, which he developed with input from Perkins and Crawford. The campaign has also introduced various homebrew modifications to spells, as well as unique death and combat rules.

We still have much to learn about Magical Bug, as Ray has yet to disclose its full range of abilities. Given the surprising developments in Critical Role episode 24, “Good Tidings,” it wouldn’t be shocking to see Ray put this spell to use sooner rather than later.