In Norse mythology, Droma was the second chain created by the Æsir, with the purpose of stopping the great wolf Fenrir, after it broke the first chain, Leding. The gods, upon checking the strength of the beast, decided to create a stronger chain than the first, to test if with this they could stop Fenrir. The wolf accepted the challenge, very confident, and allowed the gods to put the second chain. As in the first attempt, Fenrir had only to pull the chain after having put it on, to break it. Because of this, the gods, seeing that normal bonds could not keep the wolf locked up, ordered the dwarves to create a rope, unbreakable for anyone: Gleipnir.
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