Forest Spirit

Forest Spirit or Shishigami is a supporting character in Princess Mononoke. He is known as a god of life and death

in film
The Deer God "Forest Spirit" is protector of the forest and is the God of life and death. He heals Ashitaka of his bullet wound, yet interestingly leaves his curse. Later, he takes the life of Lord Okkoto and Moro. Lady Eboshi shot him as he was transforming into the humanoid-like Night-Walker which then releases his destructive body and steals the life of everything he touches, until Ashitaka and San return his head, restoring peace.

Appearance
The Forest Spirit looks like Yakul, but with more antlers and a monkey like face however, during night time he can transform into gigantic semi transculent humanoid form.