We all know the official Boneskinner lore ended up being kind of bullshit, but what if it was better? What if it actually related to the other tragedies haunting the Bjora Marches?
What if you didn't always find the soldiers who walked helplessly hypnotized away from the safety of the fort?
Lost spirits plague these lands, spirits corrupted or who have forgotten their origin...longing for a form, a body, anything. So they cling to what they can find, create a gravity of sorts pulling in any identity they can. It's a tragedy to lose yourself to such a pull, dying in the cold against the meager shelter of a tree only to find your soul diverted from the Mists to a hungry source longing for any sense of self...
And once it holds that identity, where else would it go but to the body that once housed it? Pulling souls and bones together into a shambling mass, wanting to be an animal, wanting to be a beast its bones just aren't suited for.
The mass grows, it warps as souls are collected and bones gathered, forming some semblance of the creature it once was but in a horrific caricature echoing so many pained and lost voices beneath its own, all fallen victims to the whispers of these woods that still echo off of every tree.
It's not enough though, it wants more. It needs more. It needs flesh and life and purpose that hasn't been wasted...it hunts.