Her name is Hel. She is the goddess of the Norse's underworld (also called Hel) and is sometimes called the goddess of death.
Technically there is no Norse god of evil as Loki is the god of lies, chaos and mischief but does not quite go as far as evil. Hel is the Norse goddess of death but again not evilness. The jotunns were described as evil but they were giants not gods.
Hel
The realm of Hel the goddess is also called Hel, or Niflheim (or Niflheimr). In the hall Éljúðnir.
Hel, was/is said to be the goddess of the underworld and sometimes death. Some say though, that Holler was/is the god of death because he would/does drag people into his dungeon and torture people to death. He is however, the god of illness and chaos.
Hel or Hella, Goddess of the Underworld
There is no Norse goddess of mischief, however there is a Norse god of mischief - Loki. It may be the the asker wishes to know the Norse goddess of the underworld - her name, in fact is Hel, and her domain is also known as Hel (one "l" not two).
Nike is the goddess of victory.
If you're trying to ask how was the Norse goddess Hel worshiped, the answer is "she wasn't." Not all the figures, gods and goddesses from the myths were actually worshiped or honored.
There were no gorgons in Norse mythology. However, the goddess Hel is sort of like Medusa.
Hel was the daughter of Loki and she lived in the realm of the dead, she wasn't much of a goddess though. She was more of a queen or a caretaker for the dead.
proserpine/proserpina was the roman goddess of the underworld