Majin Bone

After transforming into Dragon Bone, Shougo gets transported to a strange alternate dimension, where he fights the mysterious enemy Dark Bone. Dark Bone gives Dragon a hard fight, and drives him to the brink of destruction. Just then, three mysterious silhouettes appear behind Dragon, protect him from being defeated. The next day, Shougo gets approached by three strangers who want him to join them in protecting the Earth.

After watching Shougo get a bone crush in one kick on Dark Spider, the three men: Antonio, Luke, and Tyrone reveal that Shougo is being attacked by the Dark Bones, and they are trying to steal all the Bones from the Earth, and if they succeed the Earth could be destroyed. Shougo debates whether or not to accept their words, but when the time comes for his next fight he finds himself unable to transform for some unknown reason.

Dark Bone has appeared, but Shougo can't transform into Dragon, because his will and Dragon Bones wills aren't resonating. The Bone has the will to fight, but Shougo is unconsciously rejecting the fight. Therefore, he can't equip his Bone. Shougo stews over the questions of why he must fight, and why he was chosen for his Bone. When the Dark Bones return again and target some of Shougo's family, he makes up his mind on whether or not to battle.

The fourth bone adept, Gilbert, believes himself to be the strongest of the bone adepts because he chose to become a bone. When Dark Bones appear he thinks he has a chance to prove himself. As Leo he is able to fight evenly with Dark Bee and Dark Beetle while Jaguar takes on Dark Spider. Dark Horse enters the fray and proves to be too much for Leo, forcing the others to run to his assistance. It allows Spider, Bee, and Beetle to line up and summon a Majin, giving themselves additional speed and strength. After thoroughly defeating our five heroes, Horse declares that they've only given them a taste on this day, and they vow to return to finish the job later.

Gilbert equips Leo Bone and fights Dark Bone for the first time, but Dark Bone forms a line and summons a Majin. Leo tries to get revenge against Dark Horse but is easily defeated. Dragon agrees to fight Horse, and when he refuses to give up he powers up. Luke decides to ignore his superior’s instructions and as Shark he forms a line with Jaguar and Dragon. Shougo, shaken by his first sight of a Majin, begins to feel anxious over whether they could ever hope to beat them.

Dark Bone summons a Majin once again, but Dragon summons a Majin to oppose it. The Majin powers up Dragon and his kicks and punches manage to fossilize Bee completely. When the Dark Bone comes out of the armor he looks like a human. The Dark Bones retreat, and the fist Dragon used to land the blow fossilizes. After unequipping, Shougo realizes that the change extends to the Dragon Card, too: Dragon Bone has fossilized.

At the Bone Research Facility, Higashio informs Shougo of a shocking truth: Dark Bone are extraterrestrial life forms, and they're invading Earth to get at Dragon Bone. Shougo learns that only by fighting can he protect his friends, family, and allies. Before he can vow to help though the two strangers break into the Bone Research Facility, placing it on Red Level.

The two mystery fighters are revealed to be Victor and Gregory, and they enter the laboratory to steal Dragon Bone. The Bone Fighters other than Shougo equip and enter the Revelation Cocoon to fight Tiger and Wolf. Shougo had decided not to equip Dragon Bone anymore, but when he realizes how badly Shark and the others are struggling against Wolf and Tiger, he goes back on that decision.

The group returns from the laboratory with the repaired Dragon. Saho notices that Shougo has changed somehow. Meanwhile, Gilbert gets upset at Shougo for getting back to his casual daily life too fast. When the Dark Bones attack, Shougo reveals his resolve to protect his daily life at all costs. He bone crushes the Dark Mantis and Dark Beetle in one hit, and Dark Horse vows to return even stronger.

Gilbert throws himself into training to try and get rid of the feeling that he was fighting half-heartedly. Meanwhile Dark Horse, panicked by the rapid skill improvement of Dragon, makes preparations for what he believes will be the final battle with Dragon.

With the Revelation Cocoon destroyed, Liebert decides to grab the Dragon Bone from Shougo. She equips the Dark Panther bone and attacks. Without the Revelation Cocoon Earth's heroes can't move and fight normally.

An unconscious Shougo is rushed to the hospital where Luke vows to protect him at all costs. Liebert returns to try and steal Dragon's bone card.

Luke tells the lab that feelings power a bone and cause them to be consumed. Later on Shougo reveals a bone can be controlled and powered up if the adepts learn to communicate with it.

After becoming an adept when he was a kid, we learn Luke and his Father began to drift apart. Now they rarely see or speak to each other.

Gilbert begins to feel restless after watching Luke summon the Water Majin. He refuses to trust the others and decides to run to try and vent his frustrations.

After defeating Victor and Gregory, Leo's card becomes fossilized preventing Gilbert from being able to fight. Liebert, Morse, and Gustos are allowed to go to Earth where they learn their bones have animals that look very familiar to their bones.

Antonio increases his workload but does it at an easy pace, telling everyone he'll be able to summon a Majin when it is needed. Shougo asks Antonio how he became an adept.

The three strangers that have arrived end up being Klude, Drossas, and Vyse as Dark Wyvern, Dark Alligator, and Dark Eagle.

The adepts return to Melbourne so research can be done on the bones now that they can all summon Majins. They also wish to see what cause Leo Bone to evolve and research the new fossilized Dark Bones.