As we saw with the Death of Baldur, the Norse Apocalypse has a lot of stories that come before it; these are the little check boxes that Odin is seeking to prevent from being ticked until the last possible moment, and one of the more significant of those is Fenrir.
Direwolves get some good mention because of Game of Thrones, but for my money, none of them have anything on Fenrir. Like all the truly dangerous beings in Norse myth, Fenrir is one of Loki’s children. The wolf is so great and so destructive, that the gods realize that they must chain it up. One problem: it can break any chain ever made. The gods tried twice to keep it bound, and Fenrir broke the chains pretty easily.
The gods turn to the dwarves, the same ones responsible for forging mighty Mjolnir, for a solution. Like any great and mighty artifact of power, this chain must be made up of exceptional materials, and the dwarves don’t skimp in their list, citing impossible materials, among the necessary materials as the sound of a cat’s footfall, the beard of a woman, and the roots of a mountain.
Etiologically, this myth explains why the materials are impossible. Either they were completely consumed by the creation of this special chain, or they were always impossible items, necessary for the creation of something with impossible strength. So, ladies, you have Fenrir and the dwarves to thank for not having facial hair.
And so is forged Gleipnir. This is the adamantium of the Norse world, able to withstand any force against it. Thor’s hammer cannot dent it, and Wolverine’s claws can’t cut it. But, here’s the thing, it’s not a chain. It’s actually a silken ribbon. This is in keeping with its nature of being impossible. Nothing so thin could be that strong. Gleipnir’s thinness also explores the idea that strength goes beyond the purely physical. Willpower and honor, for instance, are not made of metal, and are, arguably, just as thin, but stronger than any known substance, a point that Tyr will soon prove.