Just off the road a man lies dead, pierced through the heart from behind by an expertly thrown and ornate dagger which remains in the body. A long strip of cloth torn from the man's shirt has been tied around his neck; on the tag end an unknown hand has written a cryptic inscription: "For Djaygo."
When you get to the next town, everyone is talking about a mercenary woman found slain in exactly the same fashion in her room at the inn where she was staying.
A secret MLM (pyramid) company that offers eternal life, but in fact it transfers the life forces of its members to those position "above". If you get high enough, (meaning you get enough new members) you start to enjoy the benefits. Maybe a willing sacrifice is much more effective for the transfer. But no one says, that a suddenly unwilling member, threatening to tell the authorities, may not loose it involuntarily... thus start people to vanish, and aged corpses are deposited somewhere safe.