Board Thread:Speculation House/@comment-15108745-20131026065056/@comment-10380701-20131026154035

Hm, I'd like to focus on the Grimm exoskeleton weapon theory.

It may explain the colored parts of Ruby and Yang's weapon. It's made from the bones of the Grimm, giving it incredible durability. However, certain parts like the blades are clearly metal.

I guess it's sort of a mix of Grimm bone and steel?