Pokemon Picross is a famous canceled puzzle game that was never officially released. The ROM surfaced in the 2020 Nintendo "Gigaleak", having been translated from its original Japanese into English. This reproduction lets you finally play and own a piece of lost Nintendo history.
Gameplay: Solve nonogram-style picture puzzles (Picross) where you fill in a grid using the numeric clues along each row and column to reveal hidden Pokemon. Logic unlocks increasingly challenging picture puzzles, making it simple to pick up but very addictive.
This is a fan-made reproduction of a game that was never released for the Game Boy Color, complete with custom box and cartridge artwork. The cartridge saves your progress correctly and runs on Game Boy Color (and Game Boy Advance).