The "helm of awe", worn by Odin in Norse mythology. It was used to intimidate enemies on the battlefield, a power which was produced by the symbol on it. It was one of the treasures the dragon Fafnir hoarded. The term ægishjálmr probably did not refer to a real, physical helmet originally, but rather originated in the use of a special kind of magic called seiðr. Seiðr could be used to affect the mind with forgetfulness, delusion, illusion, or fear. The ægishjálmr is a special subset of seiðr magic called sjónhverfing, the magical delusion or "deceiving of the sight" where the seið-witch affects the minds of others so that they cannot see things as they truly are. The role of seiðr in illusion magic is well-documented in the sagas, particularly being used to conceal a person from his pursue