See: Malice
Elder Archmage of Illusion, a fierce and ruthless spymaster. Thalia Delphine will stop at nothing to get the job done. At first was quite at odds with the party due to her having an obsession of acquiring The Key in order to help her own country, but after Fie was killed in conflict with an Aspect of Vuthul, she apparently began to see reason and started working with the party completing the key in order to take down the Forgotten God once and for all.
Was revealed by Gavriel Darrowmere to actually be a persona of Malice, who kidnapped his daughter in order to force him to do her bidding.