While this topic was originally about the Pokitto it could have relevance to the Arduboy 2 (the hardware) if it ever comes into being.
Continuing the discussion from Permission to port your open-source games to another console:
Why go to all the trouble - is it for other platforms? Almost all the games for Arduboy require NO real underlying AVR hardware support. The hardest thing might be music/sounds, but really that should be exposed as a higher level API - not by emulating the PWM subsystem. Arduino only does timer0 out of the box, and only to track the passing of time… That doesn’t have to be emulated - you just provide accurate time routines based on whatever native interrupts M0 has to tracking time.
Building a full AVR emulator on the Arm M0 platform is quite the task, but I’d think hardly necessary for the stated goals. Unless you’re doing it just for the fun of it - which is a whole other discussion. Right now I’m working on Chip8 for the Arduboy, so I know how fun that stuff can be.