19. Sonic the Hedgehog (Mega Drive)
I have something of a love/hate relationship with Sonic games, in that I love some of them and hate others. The original remains the stand-out game in the series, and the iconic first Green Hill Zone is possibly the best zone in the series as well. Going through that first level for the first time was a memorable moment, as you speed through the level collecting rings, jumping on enemies and zooming through loops. But of course, there was more to it than that, as the rest of the game was pretty damn good as well.