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Immortality is the term given to people who cannot die from natural means, whether this be due to longevity, regeneration, or other means.
1: Longevity: Characters gifted with this type of immortality cannot die from natural causes, such as old age or conventional illness, but can be killed by unnatural causes. Note that this is different from this form of Longevity, as the latter applies to those that can still age, if only slower than most normal living beings (ex. humans), and can still die from natural causes if not killed first.
2: Immortality without regeneration: Characters with this degree of immortality can survive a high degree of physical damage, though they cannot regenerate it from either.
3: Immortality via regeneration: Characters with this type of immortality can simply regenerate damage, though the usefulness of this type depends on the degree of regeneration.
4: Immortality via Godhood or protection from a deity: A character that was either granted immortality by a god, or is immortal because of its hierarchical position due to godhood, so that its divine immortality is less a power, and more treated as a consequence of its state of being as a deity. In either case, only a being of greater power than the god in question can override it.
5: Perfect Immortality: Complete and utter inability to ever die. This is typically reserved for questionable omnipotents and cosmic characters who are strong enough that dying isn't exactly high on their list of worries, even if they were capable of it.
6: Parasitic: The person attains a sort of immortality by bodyhopping, transferring their soul to another body.
7: Undead: Self explanatory. The undead generally double up with other types of immortality, often being impossible to kill through conventional means.
8: Reliant Immortality: The power to be immortal so long as a certain object, person, concept etc. exists.
9: Transcendental Immortality: Characters whose true selves exist independently from the plane where they can be killed. For example, a conceptual being doesn't die even if its body, soul, etc will be erased from existence.
10: Meta-Immortality: Entities that are not alive or dead in a conventional sense, standing outside the ordinary laws of reality, temporality, and dimensionality (of any number). If it is possible to destroy such a character, it can only be accomplished by a being of a similar or higher existence.
- Examples: All 1-A & above characters