Board Thread:Legitimate Canon Questions/@comment-27618595-20160218204106/@comment-4091815-20160218214851

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It doesn't see related what happened to Derek. I believe they use the word "evolve" in its traditional sense. The hellhound is developing within Parrish and must fully integrate in order to defeat the beast. The current situation, with Parrish unaware of the hellhound's actions, won't get the job done.