Genesis apparently couldn't handle Thunder Force IV either, according to the slowdown-ridden gameplay I just saw on YouTube. It also clearly couldn't display enough colors simultaneously, or play enough sounds that differ strongly from chainsaw noise, to prevent the game from being quite ugly.It's still probably quite fun to play. I assume it's more fun than, say, Rendering Ranger: R2. Speaking of which, check out stage 7 here, starting at 47:00: https://www.youtube.com/watch?v=Tl7D25I6yDcIt starts off slow. Keep watching. Ask yourself which aspects of this stage the Genesis could handle.Anyway, I'd still rather try Thunder Force IV, or play the even more slowdown-ridden Gradius III for SNES. Slowdown isn't good but it's better than the tedium of a generally bland game. These old consoles both relied on some terrible, crappy hardware, and they both supported excellent games and bad games and in-between games.