The Irresponsible Captain Tylor OVA

The story revolves around Duke Fleed who is a survivor of the Vega Star, raised by Dr. Umon as his adoptive son, and known as Daisuke Umon on Earth. Years after his arrival, he's faced with the threat of King Vega and his army, who want to conquer the Earth. With his friends Koji and Hikaru (and later his kid sister Maria Grace), Duke decides to fight back using his best weapon, the almighty Grendizer.

After a mysterious spaceship crashes on Earth a fleet of spaceships belonging to a race of aliens known as the Zentradi descend upon Earth sparking an intergalactic war.

Set on the distant planet Zi, the story unfolds in a world where biomechanical creatures called Zoids serve as powerful weapons in the long-standing conflict between the Helic Republic and the Guylos Empire. A fragile ceasefire holds, but rising tensions and the return of ancient Zoidian technology threaten to plunge both nations back into war. The story follows Van Flyheight, a young boy who discovers Fiona, a mysterious girl with no memory, and Zeke, an Organoid capable of enhancing a Zoid’s combat abilities. Traveling with the resourceful Moonbay and the reserved mercenary Irvine, the group searches for clues to Fiona’s past. Their journey leads them across the Republic and eventually into the heart of a renewed conflict that will shape the future of Zi.

Cobra lived an adventurous life until his enemies began to hunt him down. He surgically altered his face and erased his own memory in order to hide from his foes and lead a normal life. Eventually, he regains his memories and re-unites with his old partner Lady Armaroid and his ship Tortuga. Cobra travels the galaxy, fighting the outlaw Pirate Guild, but also fleeing the law-enforcing Milky Way Patrol.