The original title, called Pocket Monsters Stadium, was released in Japan on August 1, 1998. This version featured only 42 Pokémon available for battle, instead of the full 151 Pokémon from the Game Boy versions. The remaining Pokémon were viewable in a Pokédex, but the models lacked the required animations for battle. This version was not released outside of Japan, and as such the numbering of subsequent Japanese releases is ahead of the North America releases. This game was originally intended for the Nintendo 64DD format, but as the Nintendo 64DD was a commercial failure, Pocket Monsters Stadium transferred to cartridge format. There was also a Pocket Monsters Stadium Expansion Disk proposed as an add-on for the Nintendo 64DD but was unreleased. The first game had met widespread criticism for its difficulty, and in the sequel, the AI was toned down to make it easier for average players to beat.
