Emperor Evulz has a worldwide empire of tyranny, and only the Chosen One™ has the magic to have a chance of stopping him. So he kills the Chosen One™, but the thing with prophecies is that they must turn out true no matter what. So the Chosen One™ is immediately reincarnated as a different person, a newborn, who will grow up and develop the same powers. This happens every time they are killed, and it is a mechanism understood by the emperor and his scientists.
So logical solution would be to trap the Chosen One™, and keep them locked up forever, so they don't reincarnate and can just rot away while Evulz' reign continues.
But Evulz doesn't do that. Instead he continues a world-wide witch hunt for the Chosen One™, stages a public execution of any suspicious child he finds, and afterwards goes searching again; initially for newborn, and then for babies, toddlers and kids who are as old as the time since the last time he executed a Chosen One™.
Why though?
My reasoning is that he uses it as a tool to deal with uppity underlings. "Oh, you say you want more freedom for your people? Very well, but while I consider that, have you ever noticed that your six-year-old daughter seems to behave a bit occult? I believe I saw her put a hex on that stuffed animal. I would send the secret police after her; but if you would forget about this proposal, I could overlook it..." The emperor is also effectively changing the public opinion so that the Chosen One™ is seen as an evil, in order to make the killing justified. And anyone who disagrees might be harbouring the Chosen One™ themselves!
So, questions:
- Would that work? Are there any weaknesses to this strategy that I missed?
- Are there any other advantages of routinely killing your reincarnating enemy, and the subsequent hunt for their reborn identity?