Angrboda

Angrboda (Old Norse Angrboða 'Harm-foreboding') appears in Norse mythology as a giantess. She is mentioned in the Eddic poems only in the Shorter Völuspá (in some edition included in the Hyndluljóð) as the mother of Fenrir by Loki. However, she is also (by Loki) mother of Fenrir's siblings, Jörmungandr, the Midgard Serpent, and Hel, ruler of the underworld. Snorri Sturluson in his Prose Edda (in the Gylfaginning) calls Angrboda a "giantess in Jötunheimr" and mother by Loki of Fenrir, Jörmungandr, and Hel. As indicated following, she may be identical with Iárnvidia 'She of Iron-wood' mentioned in the list of troll-wives in Snorri's nafnaþulur.
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[Norse] A giantess and the mate or mistress of the trickster Loki. Angrboda ("herald of sorrow") spawned three monsters: the gigantic wolf Fenrir, the Midgard Serpent Jormungand, and the goddess of the death Hel. The gods abducted the children from her hall when they learned just how dangerous they were.