Placed side-by-side, the Sonics of 1991 and the current gen don't make for a stunning visual contrast.
A growth spurt of gangly little legs aside, Sonic's basic design has barely changed in twenty years, but the games they star in vary wildly, making Sonic Generations as much a celebration of Sonic's diversity as a 20th birthday party.
Two games running parallel to each other, one a glorious 2D tribute to the Megadrive, the other the awkward mishmash of gaming styles that we've come to expect from modern 3D Sonic.
The two are brought together by a 'mysterious new nemesis' (our guess - Dr Eggman's involved) who saunters into Modern Sonic's neighbourhood and sets about eradicating the very fabric of space and time.
As a result, Modern Sonic, gangly legs and all, slips through a wormhole which leads to a hub world drained of colour and vitality. It's here he meets his 16-bit counterpart, who isn't much of a conversationalist, but still the pair agree that the best course of action is to warp to the most iconic levels in Sonic history and tear them up as only they know how - in both 2D and 3D.
The quick-witted amongst you will have already worked how this arrangement has the potential to excite Sonic fans to the point of head-poppery. Imagine 2D classics such as Sonic 2's Casino Night Zone expanded into three dimensions, or the essence of latter-day fan favourites such as Sonic Adventure 2's City Escape condensed into a tight 2D package.
For now though, Sega has only divulged one of Sonic Generations' levels - perhaps the most famous Sonic level of all - the Green Hill Zone.
We've experienced the Green Hill Zone in three dimensions before (most notably as a bonus stage in Sonic Adventure 2), but this is a fresh re-imagination of the old girl. In 3D, the Green Hill Zone is depicted as being a tangled mess of 2D levels that loop back and twine around each other, combining to create the stunning image of hundreds of tiny islands stretching as far as the eye can see.
In play, this is a typical 3D Sonic game. You run across a fixed track, dodging the occasional enemy (here played by the original cast of Green Hill Badniks - hence, Crab Meats and Buzz Bombers), and occasionally chaining together mid-air homing attacks to reach higher ground.
As per tradition, the flow is periodically broken up with rail-grinding sections which in this instance take us to a part of the Green Hill Zone not previously seen - its underground caves, where you're chased by a mecha-piranha the size of Sarah Jessica Parker's nose.
2D Sonic never had these problems. Talking of 2D Sonic, his sections are undoubtedly the main attraction. As you can see from the early screenshots, the side-scrolling sections are just as graphically luxurious as their 3D counterparts, but behind the HD visuals lies a startling secret; this is the most faithful recreation of the Megadrive era Sonic games we've ever seen.
The weighting of Sonic's jumps are spot-on, and the level design retains the verticality and impish sense of exploration that made Sonic 2 and 3, in particular, so compelling.
It's the game we thought Sonic 4 would be when we first saw shots of it - a new instalment which takes everything we loved about the original trilogy and dresses it up with the graphical power of today's technology. (Not that there's anything wrong with Sonic 4, of course - but it's definitely its own game rather than a continuation of the Megadrive era).
So it looks like you'll have to take the rough with the smooth to get the most out of Sonic Generations. Producer Takashi Iizuka hopes that Generations will serve as a gateway game that will introduce older games to the world of 3D Sonic, but isn't that a little bit like Dairy Box including a new choc made out of poo and glass in the hope that people will start eating out of park bins?
Joking aside, the 3D sections aren't actually that bad - there's a great sense of speed and as noted, it's a treat for the eyes - and the 2D sections are a must for any Sega connoisseur. All in all, it's shaping up to be a strong birthday celebration for the Blue One.
We haven't been this excited about a new Sonic game since 'Sonic Twosday'.
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