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
Mythology of Lost "one of the biggest secrets" of the mythology. The producers have often hinted that the black cloud of smoke is not a monster in the traditional sense, nor is it a cloud of nanobots (as some fans have speculated). The smoke monster is established as an antagonist in "Lost" from the very first episode, "Pilot". The producers' initial plan was for the monster to represent the id, in a manner similar to the "id monster" from the 1956 film "Forbidden Planet". This idea was changed by the end of season one, when the character Danielle Rousseau describes the monster as