Hel is not a Cealtanach Spirit. Rather she is the principle Goddess of the Stormhir, who has become known to the Gaels through raids and the vibrant, terrifying paintings, on the sails of Stormhir ships.
Hel is the Goddess of death, war, and Winter. When she opens her mouth to breathe the frosts that descend from the frozen North envelope the world and turn the oceans to ice. Even the mighty Sun flees her wrath. In the deepest part of Winter the Sun stays away for weeks.
Not much is known to the Cealtanach people about how to worship Hel, or why a people would choose to worship such an obvious monster. Hel has come to symbolize distant and foreign evil – a violent and merciless force without even the balance contained in nature. Pure brutality.