Orrak

Orrak (or Aurrak) is the Luminous Eldwurm whose soul supports the universe as one of the eight pillars of creation. Among the four Eldwurms that represent the four fundamental forces, she is the equivalent of Keeper of the Light with her embodiment of light, but she is actually the strong nuclear force.

Lifespan and Immortality
Like all Eldwurms, Orrak is immortal in a sense that she can reincarnate as long as there is a suitable host body for her soul to take up residence. Upon death, she finds the next oldest dragon of her type (which is the luminous dragons in her case) before filling their soulless body with her own soul. The vessels she possesses are not immortal themselves, so they all die naturally like any living creature, but it is said that they have long lifespans and grow stronger in both physical strength and their respective elemental powers as they mature and age rather than wither into weaker dragons.

Trivia

 * Both the names Orrak and Aurrak are a reference to her golden nature. "Or" is another word for the color of gold, often used in the context of heraldry. Her latter name may come from "Au" which is the chemical symbol for gold in the periodic table.