An updated version of Hiryuu no Ken: Twin (Flying Dragon overseas), entitled SD Hiryuu no Ken Densetsu (lit. SD Legend of the Fist of the Flying Dragon), was released in Japan only, adding more characters (such as Jack, Ryu, and Gofire from the Super Chinese series), items and a new gameplay mode. It also removed the more realistic "Virtual Mode", favoring the super deformed "Quest Mode".

Playable characters are Ryuhi, Hayato, Min Min, Wiler, Shouryu, Yuka, Suzaku, Powers, Robo No Hana, Bokuchin (unlockable), Jack, Ryu, Raima, E. Quaker, Ellie, Gofire, Ryumaou (unlockable).