I'm on record finding the Sega Game Gear to be useless, but one of the better genres it could pull off was role-playing games. 
Bonus info reward: Dope box art alert⚠️ is one of the earliest infusions of strategy into the genre for Sega. While it's definitely clunky, the base building blocks of the Fire Emblem-likes are there.
Crystal Warriors
Bonus info reward: Dope box art alert⚠️You may have been able to catch this relic as a Nintendo 3DS digital download, before the eShop closed down for good.
The sprite work is totes adorable: .png)