Originally, as is now famous, Creatures, Inc. (formally Ape) found success with Game Freak and Nintendo with the Pokémon series. Creatures, Inc. later decided to make their own game adopting the 'collection' element of that series called Chee-Chai Alien, with lots of tiny alien creatures to collect from artificial light sources.
A quirk of the original game is that a real-world element is involved where the infrared port is used to point at the light sources; leaving the original game as a Game Boy Color exclusive (not even a Game Boy Advance can play it without external modification).
Creatures, Inc. later made a minigame compilation involving the Chailiens for Game Boy Advance known as Nonono Puzzle Chailien (Nonono Puzzle Chalien in the English Iwata Asks); also spun-off as Spin Six for DSiWare. However, no other game has been released in the series since.
The Chalien series
|Game Boy Color||Chee-Chai Alien|