Split/Second 2 (lost build of unreleased sequel to racing game; 2010s)
Split/Second was an action racing game developed by Black Rock Studios Limited (formerly known as Climax Racing, and Climax Brighton) and was published by Disney Interactive Studios. The game heavily focused on gameplay called "Power Play" and "Route Changer" that can either explode the environment or change the track layout respectively.
A sequel was developed at some point since because there was an ending that says "To be continued...". It was canceled in December 2010 due to new management despite appealing to the new management causing many layoffs over 100 hundred people; only 40 still remain.  However, on June 30th, 2011, Black Rock Studios was shut down. 
Despite as of now no build of the game already found. A video of gameplay was re-uploaded by BigBit ltd. The original video was uploaded by a developer, from 2011 and unlisted. There is also a video showcasing another gameplay on YouTube by a user known as FXX Rixen. However, the uploader was terminated and there have been no reuploads. Today, concept art, and screenshots is known to exist.