Rydberg has shown.

The gods can disguise their form, change their shape, are often met in
a mist, which shrouds them save from the right person; they appear
and disappear at will. For the rest they have the mental and physical
characteristics of the kings and queens they protect or persecute
so capriciously. They can be seen by making a magic sign and looking
through a witch's arm held akimbo. They are no good comates for men or
women, and to meddle with a goddess or nymph or giantess was to ensure
evil or death for a man. The god's loves were apparently not always so
fatal, though there seems to be some tradition to that effect. Most of
the god-sprung heroes are motherless or unborn (i.e., born like Macduff
by the Caesarean operation)--Sigfred, in the Eddic Lays for instance.

Besides the gods, possibly older than they are, and presumably mightier,
are the "Fates" (Norns), three Ladies who are met with together, who
fulfil the parts of the gift-fairies of our Sleeping Beauty tales, and
bestow endowments on the new-born child, as in the beautiful "Helge
Lay", a point of the story which survives in Ogier of the Chansons de
Geste, wherein Eadgar (Otkerus or Otgerus) gets what belonged to Holger
(Holge), the Helga of "Beowulf's Lay". The caprices of the Fates, where
one corrects or spoils the others' endowments, are seen in Saxo, when
beauty, bounty, and meanness are given together. They sometimes meet
heroes, as they met Helgi in the Eddic Lay (Helgi and Sigrun Lay),
and help or begift them; they prepare the magic broth for Balder, are
charmed with Hother's lute-playing, and bestow on him a belt of victory
and a girdle of splendour, and prophesy things to come.

The verse in Biarca-mal, where "Pluto weaves the dooms of the mighty and
fills Phlegethon with noble shapes," recalls Darrada-liod, and points to