In Norse mythology, who is Vidar and Hel?

Vidar is Odin's "strange silent son" and is one of the survivors of Ragnarok. He is the one who kills Fenrir. Hel is one of Loki's children. She is a guardian goddess of the realm of the dead Helheim (Hel's Hall/Home). She's actually not a frightful figure other than in appearance and was described as laying out a feast and decorating when Baldur was killed and consigned to her realm due to Loki's trickery. She's also quite fond of women and children who have died in childbirth.