So here is the thought I have. What if there was some stitching thread, but not normal thread, living thread. Thread that interacts with the world around it by pulling together the parts from dead bodies that it finds the most desirable, and creates a body for itself to use by stitching all of those parts together. The thread itself is always looking for more desirable parts, and when it finds a desirable part, it replaces the previous part with the new one. What I'm thinking is something like a Frankenstein's monster, only it's not the body that is sapient, it's the stuff holding the body together that is sapient.
I was thinking the parts begin working again upon being attached to the body, still thinking on how it does that, it could be that the thread sends energy from itself to the points of the body that it attaches, henceforth allowing the body to move. I'll think a bit more though considering that sounds a bit like last minute thought bullcrap
A suggestion: quilting. The thread doesn't just join parts together, but actually embroiders patterns over the dead parts, which it can then move by "flexing".
Giving bearhugs to the unsuspecting since 1872.