Unity is one of the most popular video game engines in the world today, bridging the gap across PC, console, mobile and even virtual reality with Oculus Rift. (fortune.com)
Umbra is also compatible with the Unreal and Unity video game engines. (gameranx.com)
From the announcement press release: «More than just a visual and technological achievement, Far Cry 2 immerses players in an entirely new kind of gaming experience, featuring a custom - made video game engine built from the ground up. (thatvideogameblog.com)