One Piece: Grand Battle is a fighting game based on the popular anime and manga series, One Piece. Although it was the 4th entry in the Grand Battle series in Japan, it was the first One Piece game released in America.
Similar to Power Stone, the fights take place in 3D arenas with various items and obstacles scattered across the stage. Each character also has a Support Character that they summon to fight with them for a short amount of time. In addition to their normal moves and combos; each character also has a Secret Attack, which upon a successful hit triggers a cinematic finishing move which can (but not always) do enough damage to instantly end the fight.
Grand Battle, like many fighting games, includes an arcade mode where the player simply fights a number of opponents in a row as well as a story mode which features brief dialogue scenes between the characters. It also includes a Tournament mode and a minigame mode.
While localizing the game in English, 3 characters and 2 stages were removed because the English versions of the anime and manga had not yet reached the story arc they appeared in. Certain stages, character profiles, and even some characters attacks were edited to remove references to events that happened later in the series.
The American version of the game features 16 playable characters, while the Japanese version had 19.