Can you play SuperGrafx games on a PC Engine?
No you can not. Unfortunately if you want to play the 5 games released for the system, you will need the SuperGrafx console. However, the SuperGrafx is backwards compatible, and will play PC Engine games. Two games do take advantage of the SuperGrafx system, but play on the PC Engine. Super Darius is one. The other was only given away as a contest prize, and is reported to have only 800-1000 made. That is Darius Alpha.