Catylketz

Catylketz was the king of the darkness dragons and the infamous brother of Quetzalcoatl. He did many cruel deeds and was eventually vanquished by his brother while attempting to seize control of the universe.

Catylketz's bloody conquests
Over a period of many years Catylketz destroyed thousands of light dragons and put at least fifty species dangerously close to extinction. His deadly missions of destruction, along with his motto "take no prisoners, leave no one alive", made him one of the most feared dragons in his time.

Catylketz hired death dragons, chaos dragons, and darkness dragons in his army.

Death and legacy
Catylketz was at last killed by his brother, Quetzalcoatl, in the final battle that would decide the fate of the universe. It is speculated he may still be alive out there, biding his time. This is supported by the fact that if Quetzalcoatl had truly vanquished him, there would be no evil or sin in the world.

Historians wait... and fear.

Powers
Catylketz had many unique and dangerous powers, one of which was his deadly breath weapon. It was a thick black cloud that engulfed his opponents and fed on their tissues, effectively reducing him to a skeleton. This worked particularly well on light dragons.