The Falkyr were created as an experiment by the Black Dragon King of Magic, Muunidyr.
The Falkyr were a combination of Werewolf, Vampire, Demon and Dragon. However, the transformation didn't always go well. When it did go well, it created an immortal beast with the best traits from each being. When it didn't, it either killed all of the participants, or it left a lump of flesh where the creature should be. No matter the outcome, they're all called Falkyr, and they were all used in one way or the other. The failed ones were fed to the successful ones to make them stronger.
Currently, there are 6 Falkyr left in existance. Each one is revered as a God, and acts independently from Muunidyr and any other Falkyr.