Zoya comes from a distant land. She has heard of an ancient object that has tremendous value. The undead army marching towards the castle has done half the job for her - the castle has been abandoned and there's no-one to keep the treasure safe. The time is right.
Zoya is an exceptional thief and has a soft spot for all things shiny, but not much else is known about her. She keeps things close to her chest and doesn't invite anyone to ask her any questions. She's never revealed secrets to anybody.