Kyousuke's younger sister Namika has been living apart from him for ten years. One day, she returns and begins to live with him again, but she has turned into an energetic Osaka girl.

Segua Kingdom has been losing the war against Ninterdo Empire but the tables are turned by the appearance of a boy called Gear. All the characters are parodies of Nintendo or Sega games such as Sonic the Hedgehog, Super Mario Bros., The Legend of Zelda etc.

In the Andromeda galaxy there's a planet of a highly developed human civilisation. The gentle Prince Itaka and another kingdom's beautiful Princess Lilia are about to enter a love-marriage and take over the throne, when they discover a strange object on the nightsky. Later it lands on the planet, and an alien, mechanic civilization invades King Itaka's peaceful country making nearly everybody their slave. On a fateful night Queen Lilia gives birth to twins, and to avoid misfortune, the nanny Tarama takes one of the babies away, and entrusts it to the gladiator Balga. They still don't know, that the children were born with strong powers, and hold the key to the fight against the enemy that's searching to destroy every human civilisation on the planet...

Based on the first Wizardry game "The Proving Grounds of the Mad Overlord", a group of characters enter a dungeon to confront the ultimate wizard to prevent him from reaching an unstoppable power. On their way they meet up with a few new friends who have their own battles to settle, but their paths lay together.