The Smoke Creatures

During The Assault on Anthur-Ro, The Ladies' Hiking Club encountered a dark demiplane as they breached the bottom level of Anthur-Ro proper. Inside, raspy ethereal voices greeted them and asked them if they were to join them in captivity: that they had been there for time past reckoning.
As a dedicated group of prison abolitionists, the group decided to release those entities without further inquiry. Vega Spritzer tore a hole in the demiplane and allowed them to escape. Short, twisted, scrawny beings, seemingly made of loosely packed charcoal and ash, poured out of the tear and evaporated into billowing smoke as soon as their bodies made contact with the air. They whispered their eternal gratitude as they vanished.
I mean, it's better than swearing eternal vengeance, right?