[Game thread] Skull Ruins Pokerole

[Dragonstrike]

I'm fine with that, as it's basically a simpler method of rolling Nathan's grab-the-shed-shell check. if DS is ok with it.

I kinda don't want this to be a straight 50-50.  I'd rather put my all into figuring out how to prevent this so it's less likely that I feel cheated if it isn't stopped.  I'm not much of a gambler.