Diddy Kong Racing Adventure is a rejected pitch made by the Climax Group for a Diddy Kong Racing sequel on the Nintendo GameCube around 2004. The project was never announced to the public in any capacity and only became known after an amateur video game archivist acquired the prototype and published a video about it in November 2016. Only the demo for their pitch was developed, in around April 2004, running on Xbox hardware as the tools had already been developed at the time.