The Echo of the Marrow

The cold doesn't just kill. It hollows you out, creating room for the beast to creep in.

For the skin- shifters of the Northern Tribe, the Winter Trials are a sacred month of psychological cannibalism. In the silence of the cold, loneliness slithers in and snipes out your spirit like a trained assassin, silent and fatal. Starvation and the strive to remain partially humanesque proved itself to be a difficult challenge as the minds of these shifters lost the visual of their human clothing. Their once intellectual minds were warped, manipulated, distorted; once soliloquies of life now simplified to feral grunts and the bare minimum of words.

That wasn't what caused some to fall and wither away. It was the loss of one's mind. The consumption of their personality. The reality as they comprehended their skin side vanishing, failing the internal war with their raging wild. It was cannibalism at its finest, the devouring of one's constructed facade to make way for something rabid, something lethal. A new identity.
...
To survive the sub-zero wasteland, a warrior must shed their humanity and embrace the rabid, lethal nature of the wolf. Elkmin is a man of iron-clad virtue and honor, a son of tradition who enters the frost of the Winter Trials to prove his worth. But when the earth gives way beneath him, he falls out of the snow white purgatory and into a darkness ancient enough to have a heartbeat.

There, he finds Echo.