Immortal Feat

Prerequisites: 1st level only, near-human variant
According to legend, a human can achieve immortality by replacing their heart with a mote of celestial radiance. The secret to immortality, including the elixirs and rituals needed to achieve it, is protected by a small clandestine sect of immortal mystics, each of whom only know one component of hte process. There are perhaps only a dozen true immortals in the world, but as many as hundreds if every tale can be believed
Ageless. You don't age, you can't be aged magically and suffer none of the frailty of old age. You can't die of old age.
Immortal Resilience. You have advantage on saving throws you make to avoid or end diseases and the poisoned condition yourself. YOu also have resitance to poison damage.