About Fenrir (and his siblings) appearance
@lycosofscribes made a very interesting point in the Norse mythology community and I wanted to answer them.
They asked why Fenrir wouldn't have his father's shape shifting abilities, and INDEED. If you take the mainstream, retold variant of the story, it does not make much sense, does it?
Fenrir, but also his siblings, Hel & Jormungandr, are the children of Loki, a half-Jotun/half-Aesir god, and Angrboda, a giantess.
Most people who had not researched Norse myths believe it is the reason why their children look different.
BUT the fact is MANY Aesirs have children with giantesses, and their children look "normal". Odin, who is half-Jotun, half-Aesir (just like Loki), has MANY children with ladies from Jotunheim, and none of them look like Loki's three special kids or are stuck in animal form.
Look at Thor, Vidar or Bragi... They're 3/4 giant too...
So why them? Why do they look the way they do?
Well, to try and find an explanation, we must go back to the earlier versions of Norse myths, before the 12th century.
And before the 12th century, Angrboda did not exist - or at least, not under that name, not in the way we know her nowadays. (This is confirmed by Rudolf Simek & Andy Orchard in both their dictionnaries)
Then, if Angrboda wasn't there, how were their kids created, you ask?
Well, there is this story of Loki eating a witch's heart and getting pregnant and giving birth to "monsters" because of it. Later versions of this story still exist, and they're very vague about those "monstreous children", but it is VERY possible that in the earlier variant of the story, this was the origin of Hel, Fenrir & Jormungandr.
With their mother being dead BEFORE they were even created, this would explain the children's appearance: why Fenrir and Jormungandr are stuck in beastly form, and why (most of all) Hel is described as "half-dead".
