Fafnir his foster-son Sigurd to kill the dragon. Regin instructed Sigurd to dig a pit in which he could lie in wait under the trail Fáfnir used to get to a stream and there plunge his sword, Gram, into Fafnir's heart as he crawls over the pit to the water. Regin then ran away in fear, leaving Sigurd to the task. As Sigurd dug, Odin appeared in the form of an old man with a long beard, advising the warrior to dig more trenches for the blood of Fafnir to run into, presumably so that Sigurd does not drown in the
Investigations into Germanic Mythology concerning resemblances of Thor and Indra were carried to extremes, therefore receiving "less recognition than they deserved." Others refute individual points of the work. Still others have commented on what they see as fundamental flaws in Rydberg's methodology. While many modern scholars object to any systematization of the mythology including the one imposed by Snorri Sturlusson, believing it artificial, John Lindow and Margaret Clunies Ross have recently supported a chronological systemization of the most important mythic episodes as inherent in the oral tradition underlying Eddic poetry. Rydberg, however, believed that most of the Germanic myths could be fit into such