These are special immortals. And I rarely have a chance to use any of my stuff in an actual campaign. I just do it as a hobby and to flesh out ideas for my writings.Do all imortal creatures gain this templete in your worlds (like demons) or only special ones?
Well, whats required for living forever tends to be continuous cell regeneration. I.e. regeneration.Why regeneration? I mean I can understand if you were thinking along the lines of Dorian Grey immortal, but most immortals from literary works (at least those Ive read) don't have immortals regaining body parts or rapidly healing, just living for ever.
Also, think Wolverine. He never ages because he is always healing.
In one of my favorite books there is also a guy who in his current 'roll' has the last name of 'Evergreen' as a joke. He's one of the few naturally occurring immortals on Earth and has been around for, oh, 6,000 years. Been through a thousand wars and never died because he'd always heal up.
So actually, almost every book with an 'immortal' in it I've ever read they did have regenerative properties.