With the wheels of Game of Thrones Season 6 beginning to turn, it looks like some theories are about to come to light. By the end of season 4, the hound gets killed by Brienne of Tarth in a rather brutal fight. But does he die? The Gravedigger theory says no to that.
What is the Gravedigger theory?
The gravedigger theory is that the hound actually survives the attacks and becomes a member of the faith, and would eventually fight in the faith's trial by combat against the accused, Cersei Lannister.
How is it valid?
One of the main reasons that this theory is valid, is because he supposedly appears in the 'Feast for crow' book (in one of the Brienne's chapters), but he apparently died in A Storm of Swords.
In the 'Feast for Crows' book, Brienne meets an elder brother in the Faith of the Seven, and says that The Hound died, but also he himself died in the battle of the Trident. This means that the man is talking about a metaphorical death, rather than a literal one. So maybe The Hound's death is also a metaphorical one?
Later on in the chapter, Brienne sees a brother digging graves. He is a described as being 'bigger than Brienne', with Brienne being over 6 feet tall. The man is also described as being lame and walking with a limp. This could be a result of his injuries before his (metaphorical?) death. Both these descriptions fit The Hound perfectly.
How can they prove it in the TV show?
They don't really need to prove it in the show. With the faith being brought in for the 5th season, and the faith needing a champion for the trial by combat, now would be a good time to simply introduce The Hound back into the fold. The High Sparrow could simply explain for a few minutes how he is still alive, and then there would be no need for any more.
So that is the basic description of the Gravedigger theory, are you are supporter of it, comment below and let me know!