Halo: Spartan Assault, the twin-stick shooter spinoff of Microsoft's popular first-person shooter series, will arrive on Steam on April 4. Developed by 343 Industries and Vanguard Entertainment, the game will cost $4.99 on Valve's distribution platform. Additionally, players can pick up the game for $1.99 on Windows 8 and Windows Phone 8 on Microsoft's store from April 3 - 9, at which point it will be permanently reduced to $4.99.

Halo: Spartan Assault first arrived on Windows 8 PCs and tablets in July 2013. The game later found a home on Xbox One in late December 2013 before landing on Xbox 360 in January. Set before the events in Halo 4, Spartan Assault explores the origins of the Spartan Ops program through 30 campaign missions in addition to weekly XP challenges. Halo: Spartan Assault will be the first game in the series to launch on Steam, and will support the wired Xbox 360 game pad as a control option. [Image: Microsoft]