The more rare, obscure, or just a guilty pleasure, the better. Maybe you grew up with it, maybe it’s just the nostalgia talking, any reason is fine.
I’m looking for a new game to play, but I’m running out of games to collect!
My favorite is games for original DMG, but you’re welcome to include Color it’ll advance games too!
Price Charting has it broken down by type. That site isn't 100% accurate by a long shot (notably it doesn't really factor in condition), but it's helpful for a rough idea. I saw it had the complete game at over $400.
I'm guessing the game is popular with collectors for being a "rare gem" of the Game Boy library (since it's both rare and actually a pretty good game). Clicking around, I see it in some rare Game Boy Color game lists—along with Shantae, which I strongly considered picking up back in the day from Electronics Boutique for like $20 and decided "nah."