Wednesday, January 14, 2026

Creature Preview: Mesmeroth

A gibbering mouther by any other name would… well, still be pretty horrible. But the renaming of this classic weird fantasy aberration was a relatively late addition to CORE20, in the course of my learning that ableist language is something that too easily hides within familiar usage.

A purple, formless creature is covered in eyes and ravening mouths.
The gibbering mouther was so-named for the endless maws that would appear across their amoeboid form, and for the confusion-inducing gibbering of the voices that would issue forth from those many mouths. Terrifying heroes since the early days of AD&D, the mouther had always seemed a classic aberrant creature to me, possessed of an alien intelligence whose very language would tear at the minds of those who heard it.

Except then during a round of sensitivity consulting on the last CORE20 alpha playtest, I was asked, “You do know that ‘gibber’ and ‘gibbering’ likely originated as a description of the speech of the mentally ill, right?” And I said, “Uh… no” — even as I realized I probably should have. I definitely wish it was something I’d known when I was the editor of the 5e D&D Monster Manual in 2014, not that it likely would have made any difference at the time. D&D is a large ship that changes course very slowly. Thankfully, though, CORE20 is a bit more nimble in its desire to improve the language and context of the game.

During the final alpha playtest of the game, the gibbering mouther thus became the mesmeric mouther, then became the more subtly named mesmeroth in the upcoming public playtest CORE20 Playtest Creature Package. The mesmeroth for our game is built on the chassis of the SRD mouther, but swaps out the traditional confusion effect of their many voices for a luring drone that draws adventurers ever-closer to their doom.

(Click on the stat block header below to download the full stat block in PDF.)


Art by Rick Hershey


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