Mysterium on the Game Boy is one of those weird little Japan-only titles that makes you go, "Wait, what is this?" at first glance. It's got this eerie, almost dreamlike vibe—like if someone took a point-and-click adventure and squeezed it into a handheld with pixelated ghosts floating around. You poke around dimly lit rooms, picking up odd items and trying to piece together what the heck is happening.

The controls are classic Game Boy clunk, so expect some trial and error figuring out how to interact with things. But there's something oddly charming about the grainy visuals and sparse, haunting soundtrack. It’s not exactly scary, just... unsettling in that late-night, playing-under-the-covers way. If you’re into obscure retro curios, this one’s a neat time capsule.