What working title did Game Freak use before the Pokémon project became Pocket Monsters?

Game Freak initially used the working title “Capsule Monsters” for the project that became Pokémon.

The idea reflected the concept of storing creatures in capsules and releasing them for adventure and battle. The project was later shortened informally to “Capumon,” but that name also did not become the final title. Because “Capsule Monsters” could not be trademarked, the team changed direction and adopted “Pocket Monsters,” which became Pokémon in its shortened international form.

The capsule concept was influenced partly by Japanese monster media, including Ultraseven, whose creatures could be stored in capsules. The eventual Pokémon design also combined collecting, trading, and portable play through the Game Boy Link Cable. “Pocket Monsters” remains the Japanese franchise name, while Pokémon is the globally familiar abbreviation. The early title is therefore a development-history fact rather than the name of a released game.