Thief's levels, however, are open-ended and well-crafted. You generally begin at the entrance to an area, and then must travel throughout, by no fixed path, meeting objectives, and then ultimately leaving. As mentioned before, you may pass guards by trickery and distraction or take them out with varying degrees of violence, which is where Spector’s Deus Ex style really comes out. While it’s obviously more fun to be naughty, you can succeed all the same by simply being unseen.