I Am the King of Monsters

Traveled to the Monster Continent? This is not the point. Become a monster? Barely acceptable. Become the chestnut ball in the Yu-Gi-Oh card? Too weak to accept. Other monsters want to bully me? Unacceptable. I want to grow stronger and evolve from a chestnut ball to an epic dragon that can cover the sky and the sun with its wings. Tens of thousands of demons knelt down to worship, and humans regarded him as a god. My name? The king of monsters!