Ape's staff included Tsunekazu Ishihara, who later became The Pokémon Company's president, and Ashura Benimaru Itoh, a renowned illustrator.

When development of this game began to falter, Satoru Iwata of HAL Laboratory was brought in to help the project.

They began with Encyclopedia Mother in October 1989, and ended with Nintendo Official Guidebook—Pocket Monsters: Red, Green, Blue (Complete Compatibility, Revised Edition) on 10 January 1997.

Shogakukan assumed Ape's role and continues to produce Nintendo Official Guidebooks in their stead.

She states that during its peak workload they have around 100 employees (including temporary contractors) to work on the creation of models and animations.

[11][12] On 16 October 2020, Creatures announced the acquisition of Ambrella, the developer of a number of Pokémon spin-off games.