Pokémon Yellow is a 1998 role-playing video game developed by Game Freak and published by Nintendo for the Game Boy handheld game console. It is an enhanced version of Pokémon Red and Blue, loosely based on the anime, and is part of the first generation of the Pokémon video game series. Along with the release of Pokémon Yellow, a special edition yellow Pokémon-themed Game Boy Color was also released.
Like its predecessors, it is a third-person, overhead perspective and consists of three basic screens: an overworld, in which the player navigates the main character; a battle screen; and a menu interface, in which the player configures their party of Pokémon, items, or gameplay settings. The player uses their Pokémon to battle other Pokémon. When the player encounters a wild Pokémon or is challenged by a trainer, the screen switches to a turn-based battle screen that displays the engaged Pokémon. During battle, the player may select one of up to four moves for their Pokémon to use, use an item, switch their active Pokémon, or attempt to flee. Pokémon have health points (HP); when a Pokémon's HP is reduced to zero, it faints and can no longer battle until it is revived. Once an enemy Pokémon faints, the player's Pokémon involved in the battle receive a certain number of experience points (EXP). After accumulating enough EXP, a Pokémon will level up. A Pokémon's level dictates its physical properties, such as the battle statistics acquired, and the moves learned.
Catching Pokémon is another essential element of the gameplay. During battle with a wild Pokémon, the player may throw a Poké Ball at it. If the Pokémon is successfully caught, it will come under the ownership of the player. Factors in the success rate of capture include the HP of the target Pokémon and the type of Poké Ball used: the lower the target's HP and the stronger the Poké Ball, the higher the success rate of capture. The ultimate goal of the games is to complete the entries in the Pokédex, a comprehensive Pokémon encyclopedia, by capturing, evolving, and trading to obtain all 151 creatures.
Pokémon Yellow allows players to trade Pokémon between two cartridges via a Game Link Cable, including the previous games Pokémon Red and Blue. This method of trading must be done to fully complete the Pokédex, since each of the games has version-exclusive Pokémon. The Link Cable also makes it possible to battle another player's Pokémon team.
Pokémon Yellow features several enhancements and changes. Including the below-mentioned inclusion of Pikachu as the only available Pokémon to start with, Pikachu is given both a voice and a personality unique from other Pokémon. It follows the player on the overworld, and can be examined by speaking to it by pressing A when the overworld character is facing Pikachu. While it initially has an indifferent opinion of the player, it can grow to love or hate them based on the player's actions; leveling up will keep Pikachu happy, while fainting frequently will make it unhappy.
There is an area in Pokémon Yellow that features a "Surfing Pikachu" mini-game. In order to play it, players must have a Pikachu who can learn "Surf", a Water-based attack. At the time, players could only accomplish this by winning a contest to get a "Surfing Pikachu". However, if players use their Pikachu from Yellow in Pokémon Stadium and beat a certain mode under the proper circumstances, they are rewarded with the move Surf, which can be used both in battle, out of battle, and in the above-mentioned mini-game. Pokémon Yellow has slightly improved graphics from its predecessors and can print Pokédex entries onto stickers using the Game Boy Printer.