The Undying Ones are individuals that were both cursed and saved by Arthe during the Sinless Night, they are immune to the effects of the Avaranna, the Dark Dawn Curse.
During the Sinless Night, Arthe in a desperate act gave mortal she deemed strong enough to resist her gift, an immortal heart. Those who received this gift became immortal and beacons of of Arthe’s power to resist the influence of Sin.
The Undyings cannot be killed by normal means, their heart is made of unbreakable glass that overflows in divine power which cures every wound of the body. Even if the heart were to be removed and the rest of the body destroyed, the body would swiftly regrow around the heart.
Capitivity
Even if their bodies are undying, they are not invincible. Over the year many Undyings have been captured, tortured and kept hidden in order to use their power against their will.