One Piece: Become the Pirate King! is a turn-based strategy game for the handheld WonderSwan console, loosely adapting the events of the East Blue Saga (along with One Piece: The Movie). Designed by Soft Machine and published by Bandai, it was released on July 19, 2000 - the first official video game under the One Piece license.
Following the game's release, five more One Piece games would be produced for WonderSwan consoles, though Become the Pirate King! remains the only one compatible with the original monochromatic system.
The game mainly revolves around path-building, with players laying tiles across a sea map. The piecemeal paths depicted on these tiles must be connected so players can reach objectives such as islands and enemy crews.
Tiles come in four basic path formations - straights, elbows, T's, and crosses - that can be rotated clockwise or counterclockwise. A tile's "strength" is determined by its texture; dark tiles (carrying "smooth" paths) can be replaced by new tiles, while light tiles (carrying "riveted" paths) stand permanent.
Players are limited to a "hand" of five tiles at any given time. After a tile has been laid, its successor must be chosen from a randomized "deal" of five new tiles.
Four modes may be accessed from the Top Menu. The "main" mode is single-player, while the others may each support up to four players.
The Story mode consists of seven chapters, adapting the Straw Hat Pirates' adventures in the East Blue.
- The Pirate King and the Great Swordsman (海賊王と大剣ごう Kaizoku-Ō to Daikengō?)
- Femme Fatale (ましょうの女 Mashō no on'na?)
- 800 Lies (ウソ Uso 800?)
- Soup (SOUP?)
- Tears (なみだ Namida?)
- A Legend Begins (伝せつははじまった Densetsu wa hajimatta?)
- The Great Golden Pirate (黄金の大海賊 Kogane no dai kaizoku?)
The Versus mode allows players to race a CPU opponent or each other across a variety of pre-programmed sea maps.
An electronic adaptation of the Carddass Hyper Battle system attached to the official One Piece card game. Supports up to four players.
- The game's story mode depicts the Going Merry as Luffy's ship from the very beginning, rather than an acquisition from Syrup Village.
- On its initial release, the game's instruction booklet was packaged with six exclusive Carddass cards, all based on the game's box-art. One used the box-art directly, while the other five depicted the individual Straw Hat Pirates.