All in all the process took about 3 weeks. There were two phone interviews, one with a recruiter, the second with a couple members of the art team, and then an art test that was reviewed during an onsite interview.
The onsite interview was comprised of 3 groups. The art leads, UI artists, and UI engineers. They went over the test, asked about your motivations and reasoning behind the choices, some standard UI/UX questions before launching into a mini whitebox test.
The onsite was held close to the end of the work day and I received an offer the next morning.