Pokémon Red and Blue are played in a third-person view, overhead perspective and consist of three basic screens: an overworld, in which the player navigates the main character;[3] a side-view battle screen;[4] and a menu interface, in which the player may configure their Pokémon, items, or gameplay settings.[5]
The player can use 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 two engaged Pokémon. During a battle, the player may choose to fight using one of four moves, use an item, switch the active Pokémon, or attempt to flee; however, fleeing is not possible in trainer battles. Pokémon have hit 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 that were involved in the battle receive a certain number of experience points (EXP). After accumulating enough EXP, a Pokémon will level up.[4] A Pokémon's level controls its physical properties, such as the battle statistics acquired, and the moves it has learned. Some Pokémon may also evolve at certain levels. These evolutions affect the statistics and the levels at which new moves are learned. Pokémon at higher stages of evolution gain more statistics each time they level up, although they may not learn new moves as early, if at all, compared with the lower stages of evolution.[6]
Catching Pokémon is another essential element of the gameplay. While battling with a wild Pokémon, the player may throw a Poké Ball at it. If the Pokémon is successfully caught, it will come under the player's ownership. Factors in the success rate of capture include the HP of the target Pokémon, whether it is under a status effect, and the type of Poké Ball used: the lower the target's HP, and the stronger the status effect and type of Poké Ball, the higher the success rate of capture.[7] 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.[8]
Pokémon Red and Blue allow players to trade Pokémon between two cartridges via a Game Link Cable.[9] This method of trading must be done to fully complete the Pokédex since certain Pokémon will only evolve upon being traded and each of the two games have version-exclusive Pokémon.[1] The Link Cable also makes it possible to battle another player's Pokémon team.[9] When playing Red or Blue on a Game Boy Advance or SP, the standard GBA/SP link cable will not work; players must use the Nintendo Universal Game Link Cable instead.[10] Moreover, the English versions of the games are incompatible with their Japanese counterparts, and such trades will corrupt the save files, as the games use different languages and therefore character sets.[11]
As well as trading with each other and Pokémon Yellow, Pokémon Red and Blue can trade Pokémon with the second generation of Pokémon games: Pokémon Gold, Silver, and Crystal. However, there are limitations: the games cannot link together if one player's party contains Pokémon or moves introduced in the second generation games.[12] Also, using the Transfer Pak for the Nintendo 64, data such as Pokémon and items from Pokémon Red and Blue can be used in the Nintendo 64 games Pokémon Stadium[13] and Pokémon Stadium 2.[14] Red and Blue are incompatible with the Pokémon games of the later "Advanced Generation" for the Game Boy Advance and GameCube.
