Onechanbara: Bikini Samurai Squad (お姉チャンバラvorteX ~忌血を継ぐ者たち~ Oneechanbara VorteX ~The Descendants of The Cursed Blood~?) is a horror themed hack and slash video game released on December 14, 2006 in Japan, February 10, 2009 in North America and February 27 in Europe, by Tamsoft and D3 Publisher as part of D3's Simple series. Styled after the exploitation films of the 1970s, the game features a campy story, over-the-top violence and gore and attractive female characters in skimpy outfits. It is the first title in the OneChanbara video game series to be released in North America.
Players control Aya, Saki and Anna as they cut and shoot through waves of undead enemies, in either single-player or cooperative multi-player mode. In single-player mode the characters can be switched during play. The game features alternative modes of play; free play, quest and survival, as well as a dress-up option which allows players to alter the player characters' clothes. As the player defeats enemies two on-screen meters begin to fill. The first indicates the current character's splatter gauge, which increases as the character is covered in blood. Once filled, the character automatically goes into rampage mode, dealing more damage but also taking more damage from enemies while gradually and constantly losing health. The second indicates how much gore is on her weapon, uncleaned swords become dulled, and if the meter is filled the character's weapon will begin to lodge in enemies, forcing the player to manually remove it in order to continue fighting.
After the defeat of Reiko, Saki regains control of herself, and the two sisters return to a somewhat more normal life. However, this newfound peace isn't set to last, as once again Tokyo is infested with zombies, and the cursed bloodline of the two sisters is set to clash once again with their own fates.