 Castiel comments to the Winchesters that he finds it amazing that he does not know what he is going to do next, and teleports away after giving them his blood.In "Survival of the Fittest", after finding his garrison wiped out, Castiel has Meg take him to the Winchesters where he explains what he has discovered.Crowley arrives and is furious to see him, but Castiel no longer has a wish to fight and when Crowley realizes he's insane, he decides to put off his feud with Castiel for a time when he's sane again.