Though Microsoft announced that Halo: Spartan Assault would release on December 24th for $14.99 on Xbox One, it's already out on Xbox One (self-confirmed!) via digital download. It's received mixed reviews, with a Metascore of 71, but at least it's right in time for the holidays. Perfect as a digital stocking stuffer.
The console version of Halo: Spartan Assault includes the all-new online co-op mode as well as the Operation Hydra expansion pack. The Xbox 360 version of the title will release in January 2014.