In the not-too-distant future, the human world has long been overpopulated. Humanity marched to the stars in search of a new home, and just as this was going on, the moon's alignment caused massive earthquakes to ripple across the world, lasting several decades. Humanity was demolished. When the land finally recovered, humanity reemerged to face this strange yet familiar world. Will we, who once lorded over this domain, still remain the masters of this world?

The crew comes upon Crown Island where the animals can talk and they makes Chopper their new king. But there are human hunters there also looking for the legendary horns that will give the person who consumes it immense power. Luffy and friends must stop them from destroying this animal kingdom.

(Source: ANN)

Mankind has traveled to the stars and come across various alien civilizations, now long dead. Upon discovering the archaeological remains of such a civilization on the planet Solo, humanity finally has its first encounter with a living alien species: the Buff Clan. When Karala Ajiba, the daughter of the Buff Clan's military leader, sets foot on the surface of Solo, the Buff Clan launches a brutal assault on the colony to retrieve her. In order to escape, Cosmo Yuki, Kasha Imhof, and Bes Jordan climb aboard three trucks, which soon transform into the giant humanoid robot Ideon. When the settlement on Solo is destroyed, the survivors board a recently discovered spaceship—the Solo Ship—and flee, endeavoring to get away from the aliens and finally find peace. The relentless Buff Clan, however, is still in hot pursuit and will not give up so easily. [Written by MAL Rewrite]

After the battle with Doakuder at Soukaizan (the "other" world where the rainbow has disappeared because of the devils), a demon world Devil came to Genseikai (human world) and stole Wataru's conscience. Because of that, Wataru's heart of justice and his memories of being Kyuuseishu (world savior) vanished. After Shibaraku and Himiko brought him back to Shinbukai (the "other" world, where Soukaizan is located), Wataru regained his memories, however his conscience was still missing. To get it back, Kyuuseishu Wataru must return to fight the devils, rescuing all of Soukaizan from catastrophe! Chou Mashin Eiyuuden Wataru is the 3rd work of the Mashin Eiyuuden Wataru TV series by SUNRISE, and is considered as a "remake" series of the previous Wataru series. It started airing from October 2, 1997, and ended on September 24, 1998, every Thursday from 6:00 to 6:30pm, with a total of 51 episodes.