UNRELEASED GAME – VAPORWARE
This game is stuck in the development limbo known as Vaporware. Few to no details have been released about its gameplay, plot, or release date since its announcement many years ago. It may or may not be in active development, but neither has it been cancelled officially.
The game was initially known as Salvation, and it was being developed using the Source Engine for PC and Xbox 360. A teaser trailer of this version was released in 2008. On October 2009, it was announced that a publisher has been found and the game was reintroduced as Scivelation, running on the Unreal Engine 3 and being developed for PC and Xbox 360, as well as PlayStation 3.
Later, it was cancelled but development restarted in 2013 for the same platforms. In Q1 or Q2 2014, the PlayStation 3 and Xbox 360 versions were cancelled and replaced with new PlayStation 4 and Xbox One versions.
Source: Wikipedia, "Scivelation", available under the CC-BY-SA License.