Lost Sybille is an ash ghoul located in the Ember Ward in Revendreth. While thoroughly insane, she is very loyal to Duke Theotar and serves him alongside his retainers, Tubbins and Gubbins. She speaks in bizarre rhyming sentences and is capable of speaking to other ash ghouls. She initially guides players searching for clues to Prince Renathal's location to Theotar.[1] During the adventurer and Theotar's activities in the Ember Ward, she guides them to both Theotar's Hideout and the Sanctuary of the Mad.[2][3] She appears to have once been a part of the venthyr in Sinfall, given the nathrezim express familiarity with her and how she has "returned" to the area. She has history with Sathrovarr the Corruptor in particular.[4]
Theotar refers to her as Lady Sybille, though whether this refers to her status prior to being banished or merely a form of respect is unknown.
During [58-60] Lost in the Desiccation, Sybille refers to Theotar and his two dredger servants as "One befuddle, two from puddle," referencing Thotar's madness and how dredgers come from Revendreth's waters.
Her name is derived from the Ancient Greek sibyls, most famously the Oracle of Delphi which was holy to Apollo, god of light and sun and prophecy (among other things), similar to how Lady Sybille is found in the Ember Ward scorched by Light.