Those who hunt.
The Adamantite Leigon
Kaius made sure there were measures in place to protect the world from any of us that got the bright idea to use our powers in ways he didn’t want so don’t using your gifts recklessly or else you will find out what it is like when the hunter becomes the hunted. Venek Travad quoted on the leigon.
Being a mark of the Legion quite possibly the worst news any Blackblood can ever receive, they are the enigmatic force left behind by Kaius to leave his children in line. The legion are monsters in their own right, manufactured in the dark void outside of known planes of existence. Once they have their mark on a hunter the only thing for certain is that however many days they have in their life they will be spent running.