Short answers, pulled from the story.
Hideo Kojima created the Fox Engine after finishing Metal Gear Solid 4 in 2008. He established the project to allow his team at Kojima Productions to develop games across multiple platforms without spending years on production cycles.
The name Fox Engine comes from FOX, a fictional military unit within the Metal Gear series. The title also reflects Konami's own logo which features a fox emblem taken directly from that same fictional universe.
Pro Evolution Soccer 2014 launched in 2013 as the first commercial title powered by the Fox Engine. It appeared simultaneously on Microsoft Windows, PlayStation 3, and Xbox 360 systems.
Konami decided to stop developing with the Fox Engine because PES Productions shifted focus toward next-generation hardware including PlayStation 5 and Xbox Series X consoles. Unreal Engine replaced the proprietary tool as the preferred choice for future projects due to changing industry demands and technical limitations.
A demo played out inside a jungle environment where a young man ran freely through the area while a horse and a dog moved alongside him. This footage served as a development sandbox rather than representing a game ready for release.