To kids, Sonic the Hedgehog is the closest thing to a cartoon rock star the world has ever seen. He has a string of hits, claims to save the world, has an attitude, and a passionate fanbase. Like all rock stars, however, Sonic has also had a sharp fall from grace in recent years, with new projects suffering unfavourable comparisons to the greatness of his first few 'albums'.

For the blue blur's 20th anniversary, publisher SEGA is doing the typical record label thing and producing Sonic Generations - but this is more than just a Greatest Hits collection. While the point is to revisit the highlights of Sonic's best adventures, it's probably best to think of it as a tribute or re-interpretations album, using today's technology to put a modern spin on the ubiquitous nostalgia.

As you would expect, the first thing fans will notice about Sonic Generations is just how many references to past titles are included here. The amount of fanservice is simply staggering - from collectible artwork, alternative music from Mega Drive, Saturn and Game Boy Advance eras, references to 'Chao in Space' and characters such as Mighty the Armadillo, Ray the Squirrel and Fang the Sniper, this game has it all.

Even the menu presentation is inspired by the original Japanese box artwork for the Mega Drive Sonic games. And to top off all the homages and re-interpretations of main stages from the franchise's history, you'll also be able to unlock the smoothest version you'll ever play of the classic Mega Drive version of Sonic the Hedgehog. Bonus.

The 'tracklist' to this retread of good old times is a collection of iconic stages from each of Sonic's major console releases - from Green Hill Zone to City Escape, all the way to Planet Wisp from 2010's Sonic Colours. There's a good mix of design, location and gameplay gimmicks for each level, and the graphical presentation is simply gorgeous throughout. Even the world map, housing doors to side-missions, smacks of Sonic Advance 3's hub stages.

Fans will forever argue which era of Sonic remains his greatest, but in Generations both Classic and Modern forms have come together, and play surprisingly well indeed. It's the Classic Sonic stages that will resonate with older fans, a perfect representation of the kind of gameplay design that was so prominent in the 16-bit games: momentum-based platforming coupled with branching paths and set-pieces that wouldn't look out of place in Sonic 3 & Knuckles.

Modern Sonic has always had a bit of a problem, in that critics tend to feel that his linear speeding doesn't work all that well, and retro fans never wanted this style of gameplay in the first place. Following the pleasant surprise that was Sonic Colours, however, it's actually pretty fun to play as Sonic's up-to-date counterpart. You're still running into the screen and using the boost mechanism, but you don't feel compelled to hold the button down, while the level design ensures you'll rarely get anywhere using the tried-and-tested 'Boost to Win' tactic.

Bottomless pits - for both Classic and Modern Sonic - are clearly identified with massive orange hazard signs, and button prompts for performing a number of Sonic's moves are displayed in case you get stuck. Better still, almost every stage offers multiple opportunities to divert from the main path, allowing you to play several times over and experience a new section each time. This freedom is a big part of the reason why people still revere the Mega Drive games; to have that re-introduced in both 2D and 3D form is refreshing, especially given the misfires that have typified Sonic's recent past.

Some of the alternative pathways are less significant than others, and a number of them require you to remember a jump cue or to gain enough momentum from enemies to access. But it's enough to mimic the design philosophies of the Mega Drive originals near-perfectly, and certainly makes for a refined 3D experience.

Regardless of whether you're playing as Classic or Modern Sonic, you'll find some pretty cool set-pieces that will either dramatically alter play, or else recall memories of similar incidents in Sonic's past. It's even more gratifying when you get to play these stages in a style that you've never experienced before: Green Hill Zone as Modern Sonic has you whizzing through caverns and smashing up Motobugs before getting chased by a huge piranha fish, while Rooftop Run Classic sees you outrunning huge barrels and clambering around a clock face to crash Eggman's blimp.

Alongside the main Classic and Modern Sonic stages, each of the nine Zones has ten side-missions that aim to tax your skills in multiple ways. You're not required to do all of them, but one must be completed in each Zone to obtain a boss key at the end of each era. These deliciously bite-sized missions are brief remixes of the main stage with added conditions: complete a stage with one ring; beat a ghost Sonic to the finish line; use power-ups from Sonic 3 & Knuckles to overcome elemental hazards. Some of these outings also feature special encounters with Sonic's friends.

The whole affair is loosely connected by a shoestring storyline that sees Sonic's past and present merging together thanks to the work of a mysterious beast called the Time Eater. This dark creature sucks the life out of time periods and dumps them in a colourless world. By the time you've completed all of the Zones and reached the end of the main game, the overall experience won't have thrilled you as much as Sonic 3 & Knuckles might have done - or even Sonic Adventure 2. When you gather a range of random stages from across a 20-year period, it's never going to be easy to piece it all together under a cohesive plot. All the same, you'll still be a left wanting after that final cutscene.

The soundtrack to Sonic Generations is just as stunning as the game's graphics, and features a whole load of remixes and re-interpretations from sound director (and rocker) Jun Senoue, electronic pop band Cash Cash, and Sonic music legend Naofumi Hataya. On top of the fantastic re-imaginations of Seaside Hill, Sky Sanctuary, Speed Highway and the other main stages, you can find reworked versions of other tracks during side-missions and menus. Dig around and you'll find numbers from Sonic Battle, Sonic Advance, and Sonic 3D Flickies' Island. Visit the Skill Shop - where you can spend earned playtime points on gameplay modifiers - and you'll even a find remix of the Competition Results Screen from Sonic 2.

As positively nostalgic as all of this is, it's not surprising to find that Sonic Generations' emulation of past greats extends to its duration. Despite the fact that there are nine main stages per Sonic, seven bosses and ten side-missions per Zone, it will take an experienced fan just a few hours to blast through to the main ending.

That's about the only blight on what is otherwise a fantastic trip down memory lane. Sonic Team should be commended for really doing its homework, resulting in the best Sonic the Hedgehog experience in at least 10 years. After this and Sonic Colours, it's time we stopped talking about the Sonic franchise as one with a troubled past. The blue blur is back, and he's rocking the platforming world once again. For fans of Sonic and platformers alike, this is absolutely essential.