he was a normal deer. he did normal deer things, before getting shot and left to die. the hunter killed simply for the hell of it.
be it dark magic, be it pure, unadulterated spite, the bones of the once-majestic creature rose with a newfound mind, eager to help those who needed it, and take revenge on the man who wronged it.
however, he found the hunter in a grave. in a blind fury, he annihilated the entire village, and crafted armor from its buildings.
the deed haunts him to this day.