Sonic Gems is something of a follow-up to Sonic Mega Collection, which was released a few years ago and eventually made its way to all three consoles. It sported the “main” Sonic the Hedgehog games, the ones considered by most to be the most important entries in the series. Specifically, Sonic the Hedgehog, Sonic 2, Sonic 3, and Sonic and Knuckles were the prime players alongside a number of side titles like Sonic Spinball and Sonic 3D Blast, as well as some extra goodies, and many felt that the only real missing key was the oft-forgotten Sonic CD. It still packed a great bang for the buck.

Apparently Sega decided they had enough content to fill another disc and reap a little more change, so Sonic Gems is the result; the yin to Sonic Mega Collection's yang – sort of. True, Sonic CD is prominently featured in Sonic Gems, but it also offers up two other major titles: a port of the arcade game Sonic the Fighters and the Sega Saturn racing title Sonic R. In addition, there are six Game Gear games focusing on Sonic or Tails.

Sonic CD is a good game, to be sure. This was, after all, the biggest reason to get a Sega CD add-on for your Genesis so many years ago: massive, dynamic levels and a crisp CD soundtrack were new territory for not just Sonic but any game at the time, and this isn't a slouch as far as gameplay goes, either. It doesn't quite feel as fresh as Sonic 3, which is a bit disappointing, and the color schemes for some of the levels are almost terrifyingly bright. But the game is fun. 

Blazing past signs that proclaim “Past” or “Future” and then building up enough speed in a few seconds allows Sonic to travel through time, into the level as it was ages ago or will be in the future. This little element really mixes up the game and makes it feel like no other title out there – and the concept hasn't really been explored much after this, either. It makes for a swell change of pace, and as a result the level design is excellent. It's loaded with multiple paths. The bosses are creative and the speed is as reckless as ever. Undoubtedly, it's a good Sonic game.

Sonic R is a pleasant surprise as well. This game never reached classic status like Mario Kart did, but it's quite a bit of fun. Players pick from several characters and race on five different levels jam-packed with shortcuts and tucked-away Chaos Emeralds. It's easy to see that this is a bit of a precursor to the breakneck levels in Sonic Adventure, and for the most part, it controls well. Straying off-course can have consequences as these characters really only like to go forward, and reverse is nearly out of the question. Interestingly, players can collect rings to “spend” on speed-boosters or unlocking hidden paths, and each character has a special ability – Tails can hover, for instance, and Knuckles can glide. All in all, it's a fun game, but once you've exhausted the paltry five levels (one of which is unlockable) there isn't much more to see.

Sonic the Fighters is a cute little exercise in seeing just how far Sonic's mascot power could take Sega. This is something akin to an early Virtua Fighter, but on a much simpler, kid-friendly level. There are a number of familiar faces to choose from, which mostly expected attacks (aside from basic punches and kicks, Tails can pick people up and drop them, and Amy Rose uses her hammer to attack). The graphics are crisp and the framerate is super smooth – it actually controls fairly well, and it's fun to try out. The main problem is that the enemy AI is really spotty; the first few enemies you'll face in the arcade mode are super easy, followed by some challenging ones, and then some really ridiculously hard fights. It feels uneven. Playing against a friend is fun, of course. It's a cute little game – but it's also on the shallow side, and I can't see this one staying exciting for more than a few hours, even with friends.

The Game Gear games are almost not worth mentioning. They're pretty bad. They're all ported in their tiny glory just fine, but they just aren't much fun at all. Included are the Game Gear versions of Sonic 2 and Sonic Spinball, and original games Triple Trouble, Sonic Drift 2, Tails' Skypatrol, and Tail's Adventures. Tails' Skypatrol is probably the most interesting of these, as it's entirely airborne with Tails collecting rings and solving simple puzzles. The others are quite forgettable, unfortunately, and serve as little more than a reminder of Sonic's history.

This whole package is very well put-together. All of the games are easily accessible and include on-screen instructions before starting, and you can even view high-res scans of the old instruction booklets if you wish. There are a number of unlockables, loading times are super quick, and you don't need to worry about any of the games not having a battery backup.

Sonic Gems Collection is a nice little treat, but mostly exists to entice Sonic fans into spending a little more cash. Sonic CD is a fine game, and Sonic R and Sonic the Fighters are definitely worth checking out, even if they won't hold your attention for too long. The Game Gear games aren't very good, but it's nice to have them here. Best of all, everything is emulated to perfection and controls just as good as they were back in the day. Even better, Sonic R looks sharper than it ever did, and the load times in Sonic CD are nearly nonexistent. This is a nice collection and fans of Sonic would do well to pick it up; everyone else probably got their fill and them some with Sonic Mega Collection. Nonetheless, Sonic CD is certainly worth a play-through – anyone would do well to pick this up for a reasonable price.

Gameplay: 8.0
Although the Game Gear games are quite bad, they aren't the main focus here. Sonic R, Sonic the Fighters, and Sonic CD are, and they all hold up well to varying degrees of fun.

Graphics: 6.0
Don't expect anything marvelous. These graphics are faithful to the originals, although the 3D games look better than they used to.

Sound: 7.0
Sonic CD sports some clear, crisp sound for its time (even if it arguably isn't as classic as the MIDI soundtracks of the other games). Sonic R sports some cute J-Pop music, and The Fighters gets by without being too notable, for better or worse.

Difficulty: Medium
Usually not too easy or too hard, the games here are satisfyingly challenging. Except for Sonic the Fighters, which is a bit unpredictable.

Concept: 7.0
There isn't much new here, but the instruction booklets and other unlockables are thoughtful additions.

Multiplayer: 7.0
The multiplayer modes in Sonic R and The Fighters are good time-wasters, but don't expect your friends to insist on playing them again too often in the future.

Overall: 7.0
There's no doubt in my mind that these wouldn't have fit on Sonic Mega Collection – it's obvious to see Sega's intent here. Still, releasing so many games in one package is a significantly better deal than some other companies re-release strategies, even if some of these are barely worth mentioning. Sonic CD is fine game, however, and Sonic R and Sonic the Fighters are worth checking out at the very least. Any fan of Sonic really ought to pick it up, and if you think you'd like it I'd advise you to pick it up at the first reasonable price you see.