Immortals

Characteristics
Immortals can look like anything. There are no unifying physical characteristics that define immortals, though if they come from the same family, there might be similar traits.

Special Abilities and Distinguishing Features
Immortals are beings that have the potential to live for many years without aging. Though they can be shot or stabbed or temporarily killed, their bodies can heal, returning them to life unless they are beheaded. In a way of balancing this remarkable ability, immortals have a very difficult time of reproducing. Impregnating or becoming impregnated by an immortal is incredibly rare. While the genes that trigger immortality seem to randomly occur in certain individuals, once that person becomes an immortal, it becomes an inherited trait. For example, there could be an entire family of regular humans, but if one of them possesses the necessary genes and triggers their immortality, then all of their children will carry the same capacity.

Immortality is something of a choice. A person could have the genes and go their entire life without triggering them and lead a normal life, dying of old age. But if that person dies an unnatural death, then they will become immortal. Immortals stop aging after their first death, much like how vampires stop aging after they are turned.

Immortals can also sense one another, though only immortals with active genes possess this ability. For example, Tig can always sense when Malcolm is near because he is a potential immortal, but Malcolm hasn't triggered his immortality yet, so he cannot sense Tig.

Lifespan
An immortal will live until their head is removed.

Cultural Description
Because Immortals are so rare and spread amongst many diverse backgrounds, there is not a single culture that defines immortals as a whole.