Kamen Rider Ace Warrior is a Superhero Paranormal fix up, published in 2003, by American writer Shuky Levy that Ten thousand years ago, a massive battle royal was fought by fifty two demons known as the Undead, each representing a species fighting for dominance over all others. The winner was Human Undead, known as Category Two of Hearts, giving domion of the Earth to humanity. In the present day, archeoligists discover the sealed Undead, and accidentally set them free. Thus, a new Battle Royal begins.
