Granted, considering the poor state of the Radeon R9 290 on Linux, AMD might not be in an immediate rush to push Mantle on Linux but it's great to see game studios taking a greater interest in the API spawned by AMD. Mantle is an alternative to Direct3D and OpenGL and AMD claims it reduces CPU overhead, allows greater control of the graphics hardware, allows all hardware features to be exposed, supports new rendering techniques, can handle direct GPU memory access, and better performance all around.
The latest backer of the Mantle API is now Rebellion, the UK-based developers that are behind titles like Sniper Elite: Nazi Zombie Army 2, Aliens vs. Predator, and Rogue Trooper. Rebellion's CTO commented, "we're excited about the possibilities that Mantle brings to PC gaming and the industry as a whole." Rebellion will begin shipping games with support for Mantle in 2014 and their launch title with the support in their Asura engine is Sniper Elite 3. With Asura 3D game engine powering all of the company's titles, all future games will be supported by Mantle.
Additional comments about the game studio's Mantle adoption can be found via their company web-site. Now it's just a matter of when the Linux support will arrive.