Continuing our Sonic season after the announcement of Sonic Unleashed, here we take a fresh look at the vintage 2D Sonic games to bring you the definitive retro-reviews of 2D Sonic.

Note: The scores here may differ from our reviews of the Virtual Console or Xbox Live versions. Think of this instead as a one-off look at the old Sonic world, without modern platforms necessarily in mind. Most gamers will be familiar with the Mega Drive/Genesis original, so we'll start with the lesser-known 8-bit versions before moving on to Genesis (and more).

Sneakers at the ready. Here we go...

Sonic The Hedgehog (GameGear/Master System)
With the gulf in technology between Mega Drive and Master System, the original could never be ported directly across. So, instead of delivering a cut-down version of the first game, Sonic Team made a new game from the ground up.

The gameplay is essentially the same, with rings to collect, enemies to jump on or roll into and spiked pits to navigate past safely on your way to the boss encounters before freeing your trapped friends.

Several zones from the 16-bit version return, including Scrap Brain, Labyrinth and, of course, the classic iconography of Green Hill Zone (pictured below). The movement of Sonic is more basic on the lower-spec hardware, with no rotation. In other words, he's always standing upright as he speeds over the undulating terrain. But it's still very fast and the single 'running boots' power-up from act one is a superb moment of liberation, especially when combined with the invincibility bonus.

Above: No multi-layered backgrounds, but the art style remains intact

The six Chaos Emeralds are hidden throughout the regular stages, with the bonus levels only used for extra lives and continues. Finding the emeralds is a real challenge but that's the only way you'll get to see the true ending.

As an example of game design triumphing over limited tech, it's hard to beat. There's so much personality in the levels, so many memorable enemies like Crabmeat and Buzzbomber… in fact we can't understand why Sega was so quick to abandon the original enemies, especially when Mario still seems to meet Bullet Bill, Goombas and Bloopers in every new game.

Sure, as with the 16-bit version, you can finish Sonic 1 in a single hour, but it never gets dull, even after years of repeat plays. Few games can stand up to 16 years of scrutiny, but this one certainly can. Beautiful.