One way to think of it is that every mortal has a "Call of Death" ability
that grows as they age and opposes all healing. It would also serve as a
negative modifier on physical and mental abilities. Eventually, it will grow
so large that you won't be able to find a healer who can beat the threshold.
That's for the people with the simple destiny of "mortal." Heroes, of
course, have other banes that will get them, even if they managed to divest
themselves of the Call of Death...
No doubt, each culture would explain it differently.
Peter Larsen
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