Immortality grants its wielder the ability to survive any fatal condition, allowing them to recover from death and assume normal functions in a matter of hours.
- Nathan displayed this ability until he sold it to Seth in the Christmas Special.
Nathan used this power to recover from death multiple times.
Upon dying, the user's body automatically repairs itself to its pre-death state; the user then wakes up perfectly healthy. Although, Nathan defecated himself and seemed to have a bad stomach/guts after being revived for the first time. This indicates that the user will not have the stomach for death the first time, but they will gradually get over this. However, the power does not work if the user does not die, so physical injury that does not lead to death will either have to heal on its own or - in the case of a stroke, for example - not at all. Whether it affects aging, however, is unknown.
If the user of this power takes drugs, they become more mortal when they were before they had the power of immortality, and they may die permanently.
With this power, Nathan survived:
- In an alternate timeline, Nathan was killed by Tony when he went on a rampage, as Curtis was not there to stop him. However, he did not get killed for good, as he stated he was half-dead and his injuries had not fully healed.
- Falling off of a building and getting impaled by a metal fence.
- Getting impaled on a metal pipe.
- Getting brutally beaten to death.
- Shooting his head open with a revolver.
- On one of Superhoodie's security camera feeds, titled "The Birthday Boy", Nathan sets off a smoke alarm in the Community Center and has to turn it off before Shaun arrives. He climbs up on a railing and manages to deactivate it. However, he falls in the process, breaking his neck.
The only time immortality proved itself ineffective was when Brian used his lactokinesis to wrap mozzarella around his cortex, resulting in permanent brain damage and death of Nathan's mind and leaving him into an immortal shell.
A sub-power of immortality is - as Nathan discovered in Episode 2 - the ability to see the souls of the dead. This power was only activated after Nathan died and came back to life, which means he could see spirits of the dead as he had technically died himself. Although this is a powerful ability, it is limited by a few factors; he can only see the spirit within 24 hours of their death, and unlike typical ghosts, the apparitions Nathan sees look like normal physical beings. In fact, he doesn't even always know that the people are dead unless they tell him or if he actually see's them die, and they also possess the ability to move at will.