Best I can tell, Epiphany is designed as a co-processor, so it's not booting the OS and relies on a host (like an ARM/x86) to run the show and issue commands.

Best I can tell, Epiphany is designed as a co-processor, so it's not booting the OS and relies on a host (like an ARM/x86) to run the show and issue commands. The Epiphany cores have significantly more functionality than GPU cores, so they're useful for things beyond computing FFTs and other number-crunching tasks. For example, you could map active objects one-to-one onto Epiphany cores.