The rule of ONE PIECE DANCE BATTLE is simple. Players collect various characters of ONE PIECE, form dance teams and battles by dances on map. A story of ONE PIECE and the relationship between characters are not important in this game. Characters fighting against each other may join the same team.
Players can get new characters by achieving quests, win dance battles, and gacha system(*gacha...the vending machine which characters appear at random. General virtual goods sale form in Japanese online games, social games, and mobile games).
Because ONE PIECE was very popular contents, various social games/mobile games were released from the Futurephone era.
Bandai Namco games released a new mobile social game of popular Manga/Anime "ONE PIECE" in GREE
Popular manga ONE PIECE forms original game community in Android
However, I think that ONE PIECE DANCE BATTLE is luxury most. At first, this is full 3D title, all 3DCG are high quality and dance motions are smooth. Above all, characters dancing are very cute and funny! There are a lot of kinds of characters, and even bit parts are reproduced in 3DCG. This is a game that enjoy to see ONE PIECE characters dancing.