Pip is the name of the main character that the player in Spirit controls. He was known as a simpleton among the group of shamans he learns with until chosen to carry the weight of a very important task of fixing the imbalance between his realm and the Spirit realm.
The shamans he lives with are tribal and do rely on defenses like armor for the missions they do carry on. The mask aids them in a powerful presentation on the hierarchy of apprentice to master.