I would like to talk shortly about Will’s three hallucinations: G. J. Hobbs, Ravenstag, Stag Man.
Ravenstag is the first thing Will starts seeing, right after being exposed to Hannibal’s murder of Cassie Boyle, who was impaled on the stag head with the crows flying around the body (Apéritif). The hallucination of Garret Jacob Hobbs Will sees for the first time in the next episode after killing him, which means he sees him in Amuse Bouche. Stag Man is for the first time seen by him in Savoureux, when he starts to understand that Hannibal is the Copycat, which is the finale of the season one.
According to Bryan Fuller’s words – Ravenstag represents Will’s connection with Hannibal.
It is a creature connecting Will with Hannibal, e.g. Ravenstag was the one, who gave Will clues about Hannibal being the Copycat – by burning in Relevés, in the way how Georgia Madchen died.
Stag Man is the representation both of Hannibal and Will’s dark sides and to show how it works with Ravenstag figure, I am going to remind Will’s dream from Shiizakana of which I have already written on my blog (here): Hannibal is bounded to a tree, Will control the situation and Ravenstag helps him to kill Stag Man, not Hannibal. In the scene from the series’ finale – The Wrath of the Lamb – Hannibal is indeed bonded, and Will achieved this through Hannibal's love for him. Rejected, Hannibal preferred to be truly tied down and wait for who knows how long for Will rather than remain free but alone and so Will's subconscious resulted in him persuading Hannibal to admit who he really was, just as he had dreamed about it.
Since the situation of Ravenstag and Stag Man is quite clear, what about G. J. Hobbs’ hallucination? According to Will’s words from Amuse-Bouche, he doesn’t consider Hobbs his victim, he considers him dead. And yet, in Rôti, he seems to be truly desperate to hear from Hannibal that the hallucination is real:
I believe that the answer is in the same episode, Abel Gideon, whom Will sees as G. J. Hobbs, tells him while observing Alana, “If I kill her... like he [The Chesapeake Ripper] would kill her... I wonder if I could understand him better, hear the cold drips in his darkness, watch the world through his red haze. I wonder if then you could finally understand who you’ve become”, because that’s when Will shoots him. In my opinion his hallucination of G. J. Hobbs is the personification of his fear of letting his dark nature to surface, to become a killer, since “It’s hard to shake off what’s already under your skin”.