The story follows Elk, a bounty hunter in some strange futuristic world. On this world archaic but advanced technology exists side by side with primitive attitudes, beasts and magic. In other words it's got a bit of everything. It also has an evil conspiracy who are able to produce powerful monsters called chimera, who can also appear as human. Naturally it is not long before Elk has rescued a young female beast-master and gained himself some serious enemies.

In the original storyline as aired in Japan, Dairugger XV was simply an exploration robot, as well as an intended peace-keeping force. The Earth is in a time of prosperity. The president of the Terran League (the "Galaxy Alliance" in Voltron) launches a mission to explore beyond the galaxy. After commencing its mission of exploration, the starship Rugger-Guard is attacked by a ship of the Galbeston Empire. Dairugger, the super robot, is deployed in order to defend the Earth. It is somewhat by fate that they must help the people of Galbeston find a new planet before it explodes, and liberate it from its despotic Emperor. In the Japanese version, it does not have anything to do with King of the Beasts GoLion, as opposed to the U.S. version, Voltron: Defender of the Universe. There are three assault team units: Land, Air, and Sea. There are a total of 15 parts referred to as "Rugger," which can combine together to form the super-robot Dairugger. The design of the 15 separate Rugger units came from the sport of rugby, since 15 players are required to form a rugby union. The U.S. version would rename the "Galbeston Empire" to "Drule Empire," along with editing a fair amount of violence and sexual content to keep the show safe for general audience broadcast.

Several generations after the original Yatterman series, Leopard lives with her mother and guardians, Dorothy, Voltkatze, and Elephantus, just outside the prosperous Yatter Kingdom. She lives a happy if impoverished life, unaware of her ancestral ties to the infamous Doronbow Gang, until she discovers a mural of Doronjo, Boyacky, and Tonzura in a sealed off area of her home. It turns out that Dorothy, Voltkatze, and Elephantus are descendants of the villainous gangsters, which is why they have been forbidden from entering the hero Yatterman's Kingdom! At first, Leopard vows to never engage in villainous actions like her ancestors, but new circumstances may mean that she must go back on her word, donning the identity of villain in search of true justice.

In the wake of a third world war which left Japan in ruins, an organization known as Vischio seized control of Tokyo and renamed it Toshima. Taking place in its back alleys are battle games known as Igura, overseen by the Vischio, in which contestants battle and bathe in each other's blood to earn the chance to go up against its tournament's king, Il-re. Igura is not the only fighting tournament around; Bl@ster is a similar yet vastly different game since it prohibits murder and the use of weapons. The only way to win is by knocking out the opponent. Akira, a young man isolated from his family, is known to be undefeatable at Bl@ster. However, his life on the top is shattered when he is accused of murder. Unable to prove his own innocence, all hope is seemingly lost... that is until a mysterious woman named Emma appears and offers him a chance. Now, to regain his freedom, Akira must participate in Igura and ultimately defeat Il-re.