Which 1998 Pokémon game was designed around Pikachu following the player?

Pokémon Yellow was the 1998 Pokémon game designed around Pikachu following the player.

Released in Japan on September 12, 1998, Pokémon Yellow is an enhanced version of the first-generation games. It was influenced by the television anime, giving the player Pikachu as a starter and placing greater emphasis on the relationship between the player and the Pokémon.

Unlike Red, Green, and Blue, Pikachu follows the player outside its Poké Ball and reacts to the player’s actions. The game also includes encounters with the anime-associated characters Jessie and James, while the original three starter Pokémon can be obtained during the adventure.

Pokémon Yellow was released internationally in 1999 for the Game Boy. It is sometimes described as a remake, but it is more precisely an enhanced version of the first-generation formula, combining game mechanics with elements popularized by the anime.