This isn't at all imaginative, but I would rather just have the artifact be a powerful ward that radiates a magical aura negating forms of mind control / telepathy / what have you. No need for anyone to 'live' inside it.
I understand that that would break a number of story lines, but I'd rather accept a magical macguffin than endure the insufferable Emperor Exposition and his absurd backstory.
in the fact, i am curious that how many players see the emperor's true appearance the reaction is -- "oh, my God! what is it !!!?"
this should be interestring to have a survey -- "happiness index"

as i was said, this chess game is setting by the existence who can order withers.
i do not think the existence's taste is so bad to ruin players' feeling.
a true love is the core award for the players, not a tease to the players.
this should be a big inducement that encourages players stop game play after they finish act 2 :roll: