Japan’s first Pokémon Stadium game allowed 40 Pokémon to be used in battles.
Pocket Monsters Stadium was released in Japan for the Nintendo 64 on August 1, 1998. It brought Pokémon battles into a three-dimensional console environment, but its playable roster was limited to 40 of the 151 species from the original Game Boy games.
The game had originally been associated with the Nintendo 64DD, but it was ultimately released on a standard Nintendo 64 cartridge. Players could connect the game to Pokémon Red, Green, and Blue through the Transfer Pak, allowing Pokémon from the Game Boy titles to appear in the console experience.
This Japanese release is easy to confuse with the internationally released Pokémon Stadium. The later game, released in Japan in 1999 and overseas in 2000, supported all 151 original species and offered considerably more content. The 40-Pokémon figure belongs specifically to Japan’s first, limited-roster Stadium title.