User blog comment:B214/Volume 22 spoilers/@comment-50.139.232.230-20160726222354/@comment-9595671-20160727060510

That's one theory that could explain it and why the Rating Games became so corrupt, especially since they could turn it up or down during an actual game and trick others into thinking they're either holding back.

Though I also have another theory that could explain it. When the Rating Games were first made, only pure-blooded devils were able to play until their first few reincarnated devils reached high-class and could make their own peerages.

So maybe the King Piece isn't linked to a Devil's life like the other pieces, but more like a magical charm you could take on or off. So if a Devil didn't want to their King Piece in a fight, they could just eject it until they wanted to use it again.