Chee-Chai Alien

Chee-Chai Alien is a Game Boy Color exclusive game where the player collects aliens, known as Chaliens (Chailiens in Japan), from artificial light sources using the Game Boy Color's Infrared Port, which came packed with a peripheral to amplify the infrared signal. Since the Game Boy Advance/SP have no infrared port, the game gives an incompatibility message if it is played on a newer Game Boy model. It was developed by Creatures, Inc. after the success of Pokémon. The player can play minigames with their Chaliens, and extract their dark matter (as part of removing 'white space') to gradually progress through the story.

Chalien Selector
Menu is an unused interface where the player can select Chaliens. It can be accessed by using the Gameshark code on the title screen. There are 127 entries. A number will appear on the screen marking which entry the player has selected (the numbers range from 000-126). The Chaliens are not in the order they appear in the Space Research Notes and are ordered here by index number.

Use left/right on the D-pad to scroll backwards or forwards, respectively. Use up or down to flip the Chalien vertically. The player can also select special characters such as Rabuta (a secret Chalien based on Nintendo's Love Tester). 38Vk_bE1Z7Q

Placeholder Chalien
There is a placeholder Chalien (index number ) without any sprite called Bubēro (ブベーロ). To obtain it, the Gameshark code can be used on the main screen (where the player can choose to catch Chaliens, view the Space Research Notes, etc.) to force the player into the interface as if they just obtained a Chalien a while after the code is turned off. Bubēro has no minigame. Trying to play a minigame with Bubēro brings the player back to the title screen.