Board Thread:Lore Discussion/@comment-10324940-20130602034026/@comment-17624520-20130918192656

What if the undead condition wasn't so much a random occurrance as we think? What if the condition was intentionally inflicted? It seems to me that the undead condition would be an effect, or defense mechanism of the Dark Soul.

Some speculate that humanity was derived from the pygmy, who found the Dark Soul, and that the Age of Dark is synonymous with the Age of Man. If that's true, then the Dark Soul may have incurred the condition when Gwyn linked the fires; Possibly in an attempt to actively counter Gwyn, who had actively interfered in the Age of Fire's waning and the Age of Dark's waxing.

Just a theory, but I think it fits. Whether the condition is hereditary or not, though, I'm not sure. Perhaps the Dark Soul universal in mankind, but is clearly more dominant in those who become Undead after death.

Though whether or not it's genetic, the condition could then be equated to a geas; One given by the Dark Soul, instructing the Undead to seek out Gwyn in Lordran. Assuming that the Undead are intentionally so, following the geas could hold back the condition from hollowing someone completely while ignoring or failing it could speed the process along. This could explain why the Undead/Hollow people you encounter in Lordran never left: They simply didn't want to.