Halo: Spartan Assault originally launched on PC last June as a Windows Store app. However, Microsoft is taking its most valuable franchise onto Steam on April 4, giving more PC owners a chance to play through 343 and Vanguard's twin-stick shooter.
Spartan Assault features a story that takes place between the events of Halo 3 and Halo 4, centered across 30 missions. The game will contain Steam achivements, weekly challenges, and leaderboards. Spartan Assault will include support keyboard/mouse, touchscreen support with virtual joysticks, and controller support.