Microsoft has confirmed that Halo Spartan Assault will indeed be playable on Xbox 360 and XBOX One sometime this coming December. Previously, Assault was only available on select Window devices (WP8 and tablets). Unfortunately, multiplayer crossplay between 360 players and XBOX One players isn’t likely.
Assault is a twin stick shooter that takes place between the events of Halo 3 and Halo 4. The game focuses on special Spartan Ops missions during the cease fire between the Convenant and the UNSC. 360 owners can check out Halo Waypoint for more.
And exact release date and price have not yet been announced. However, a safe bet is probably something around a $15 price tag.