Years ago I inherited my wife's family's Game Gear. After a recap, and replacing the backlight, I started tracking down games to play on it. It's been great exploring a whole library of games that I skipped out on as a kid! (I was a Nintendo kid) Now I have a nice little library of carts to play on this beast of a 90's handheld.
My favorite game for Game Gear is Batman Returns and I never hear it talked about! It's gorgeous, it has grappling hook based action gameplay. Every stage has two options to play through so you don't get bored playing the same stages every time you power in on. And its very challenging but still beatable. I recommend it!
Yes yes yes and the big rubber duck boss!!