It has been 1000 years since Trunks bravely defeated the androids 17&18, and brought peace to the world. The world is finally starting to heal, but the bravery Trunks showed in battle was remembered forever, as the legend of Trunks was passed from generation to generation. As trunks grew to legend so to were spherical houses, and jet bikes, as the old homes were torn down, and replaced with rectangular houses, and with Bulma long dead and gone jet bikes were replaced with bikes with wheels. The world had changed much since Trunks time, But unknown to this new world a war was being waged to decide the fate of the wish granting holy grail.
So I deleted things unnecessary to the story, and gave ch 1 a revise.