One Piece: Become the Pirate King! was the first of six One Piece Wonderswan games and the only one released for the original mono system.
It is an strategy RPG game revolving around pipes and playing cards. Your task is to construct a path across the water logged area to the enemy's base using pipes. Along the way you may encounter surprise enemy attacks and these are also dealt with in a battle of pipes but on a much smaller scale.
The graphics they use the manga illustrations to make the most of the black and white display.
The Story follows the events of East Blue Saga to the Loguetown Arc, It also features the events from the One Piece: The Movie