Yûki Nakao

In a post-war alternative timeline, Japan is divided into the North, controlled by the Union, and the South, controlled by the United States. A mysterious high tower rises within the borders of the Union. Three high school students promise to cross the border with a self-built airplane and unravel the secret of the tower.

After falling through a time-slip, Yusei Fudo (who has just had his powerful card stolen by a mysterious stranger) meets with Jaden Yuki and Yugi Muto, who agree to help Yusei defeat the evil Paradox, who is planning to destroy Pegasus before he can invent Duel Monsters.