Ellison was sent by his masters to infiltrated Mantor's Library, together with fellow cultists Tibeem and Spernik, who had another mission. Ellison's mission was to recover lore about the Pool of Radiance under Valjevo Castle. He finally identified three books of interest and thieved them from their owners. However, in escaping Phlan, he suffered so many injuries that he came close to death.
After he escaped from Phlan, he met with the black dragon wyrmling Rythnax in his lair. However, they were confronted by an adventuring party hired to recover the stolen books. In the fighting, Ellison was likely killed or captured.
Ellison believed himself to be a descendant of one of Phlan's noble houses and for this reason accepted the mission to Mantor's Library so he could research this.
He despised Rythnax.