The Game Gear married the best parts of the Atari Lynx (a powerful processor, a backlit color screen) with the best parts of the Game Boy (higher screen resolution, a better price, familiar game franchises). It was, in its day, the premium portable gaming experience. Though not every Game Gear release holds up today, its brief tenure on 3DS before SEGA gave up due to low sales saw quite a few greats make their way to Virtual Console, all presented with loving affection by retro gods M2.
SEGA brought Tetris to Japan in the arcades before it became a home console phenomenon, so it makes sense that they'd have created the first great Tetris clone. Columns' match-three gameplay makes this basically the mother of all iOS games.
Shining Force: The Sword of Hajya
A legitimate version of Shining Force, this ambitious strategy RPG may not offer the same depth and visual quality as its console siblings, but it's still worth your time.
This great-looking adaptation of the popular arcade and Genesis series put everything on Game Boy to shame in terms of visuals... and it played pretty well, too.
Sonic the Hedgehog
While ostensibly a port of the Genesis game, Sonic on Game Gear actually adapted the Master System version, which was its own distinct — and excellent — thing. Definitely worth playing, even now.
Sonic the Hedgehog 2
Another total overhaul of a much larger game and all the better for its willingness to pursue originality, Sonic 2 is really every bit as good as you could ever hope for a portable 8-bit take on the blast processed megahits to be.
A huge departure for the Sonic series, this Game Gear exclusive ditches the speed in favor of exploration. This is the closest Sonic game ever came to feeling like a Nintendo franchise, and while it's different, it works quite well. Recommended.
SEGA's Game Gear had two great strategy games; this is the lesser-known of the two, since it doesn't have the name "Shining Force" attached. Don't think poorly of it for its lack of franchising, though; there's a solid game here.
Defenders of Oasis
Even though the title and Arabian Nights theme of this RPG would suggest it's related to Legend of Oasis, it's not! But that doesn't mean you should scorn it; it's a great little portable adventure.
Dr. Robotnik's Mean Bean Machine
Hey, so this is Puyo Pop, except with a Sonic the Hedgehog theme. Totally worth playing, provided you enjoy both of those series. (Ironically, Nintendo's own reskinning of the game, Kirby's Avalanche, isn't available on 3DS Virtual Console.)
Dragon Crystal has the distinction of being the first-ever portable roguelike game. As such, it's pretty simplistic, but it's a decent enough adaptation of the genre and a good introductory piece for anyone interested in learning more.
Sonic Drift 2
While it doesn't look as good as Super Mario Kart, this Sonic-themed racer plays well and remains loads of fun despite its age and fundamentally low-spec tech.
Sonic the Hedgehog: Triple Trouble
An entirely original Game Gear creation as opposed to a radically overhauled Genesis conversion Triple Trouble doesn't have the same oomph as Sonic and Sonic 2 for Game Gear. It's decent, but it's missable.
Vampire: Master of Darkness
Save Your Cash
G-LOC: Air Battle
Basically a portable flight sim, a la Top Gun for NES. Kind of neat in its own way, but ultimately it hasn't aged well and lacks even the graphical punch of Lynx's equivalent, Blue Lightning.
Despite sharing a name with Sonic 3D Blast, about all this game carries over from that console title is Sonic's 3D-rendered look. It's a clumsy, awkward, and not particularly fun traditional Sonic 2D platformer with protracted first-person bonus stages.
Minato Giken/SEGA, 1995
One of several isometric Sonic games released through the years, this early attempt to bring the franchise into the third dimension feels pokey, clumsy, and decidedly un-Sonic-like.