Ever wondered if your Game Boy's buttons were acting up? This weird little Japanese cartridge is basically a controller tester—you pop it in, mash some buttons, and it shows you exactly what's registering (or what's not).

It's not exactly a "game," more like a diagnostic tool disguised as a cartridge. But if your A button's been feeling mushy or the D-pad sticks, this thing will call it out. Kinda niche, but weirdly satisfying when you need it.

Definitely one for the "obscure Game Boy oddities" shelf.