Here is the list of steps you need to do in order to get the Dragon Mythirians

  1. Get friendly faction to the towns in the dragon zones.
  2. Finish the quest A History in Stone (Alb), Heir to a Lost Homestead (Hib), Battles in the Mist (Mid)
  3. Finish the quest Moran the Mighty (Alb), Maldahar the Glimmer Prince (Hib), Yar the Firstborn (Mid)
  4. Finish the quest The Great Hunt to kill the 4 mini dragons in the dragon zone.
  5. Finish the quest to kill the main dragon in the dragon zone.
  6. Finish the Dragon Armor quest
  7. Finish the Dragon Weapon quest
  8. Get the Dragon Myths & Legends