Mystic Knight

Mystic Knight is a legendary figure who was given that name as described in the New World's many folktales.

Appearance
As its name implied, this person should be dressed as a knight of some sort.

Background
In the fairy tale, the person was referred to as a Mystic Knight who was known for riding a Trihead Dragon.

The Bloody Valkyrie Arc
After discussion with Momon came to an end, Theo Rakheshir would remember stories about infamous individuals who carry a myth of their own. The Mystic Knight was among the people he believed to be real.

Abilities and Powers
This knight is most likely strong as it was capable of having a Trihead Dragon under its control. Moreover, the knight has the capacity of being able to freely ride a powerful dragon, the type with multiple heads.

Trivia

 * Similarly to that of the Goblin King, this legendary being is also a rider of Dragons.
 * When someone inquired Maruyama whether there is a corresponding arch-rival to Platinum Dragon Lord on Twitter, Maruyama states that there is a multiple headed dragon, but then says that it is not a God. This could confirmed on the notion the a Trihead Dragon does exist in the New World and that the Mystic Knight may have rode one before in the past.