Pokemon Crystal - Dunsparce Edition is a hack of the original Pokemon Crystal.
Many improvements have been made such as all 251 Pokemon being available to be caught legitimately, new moves, new type changes, and so on.
Please patch this to an existing Pokemon Crystal ROM using a program like LunarIPS.
ROM / ISO Information:
Database match: Pokemon - Crystal Version (USA, Europe) (Rev A)
Database: No-Intro: Game Boy/Color (v. 20180815-131105)