Usagi Ooyama

The dead return to life as cruel predators - the so-called "returners" have spread all over the world. Only a few survivors succeeded in escaping from this madness. They are submerged in remote areas, because the cities were completely occupied by the returners. There is only one person who still daggers in the cities: the Undertaker. A dark hero, a champion of the battlefield and equipped for the world after the apocalypse, starts his own personal revenge campaign.

The Waller Empire destroys the planet Clin in search of water for its deity. Two Clinian children, Spielban and Diana, escape to Earth aboard the Grand Nasca. The two grow up during the long journey and don High Tech Crystal Suits to defeat the Waller who have come to Earth in search of more water. Spielban must avenge his dead mother Anna and his homeworld, and find his missing father Ben and older sister Helen. Unknown to Spielban at the start of the series his father and sister have been made members of the Waller against their will.