#1 His gimmick is dark and suited to a heel

Corey Graves always said that Black represented 'the left hand path' or one not taken by most of the conformed in society. Since he represents an alternative way of thinking to the norms of society, he might be presented as a cult-like figure or anarchist type due to his ways of thinking. In terms of representation, his has been more focused on his wrestling thus far and less on his character. He might share similar rhetoric of Killer Kross in Impact, or he could form his own way to bring his message to the masses.
Unfortunately for those with many tattoos, they were previously represented unfavourably in society as recently as 15-20 years ago. Only more recently has it become something truly accepted throughout all levels of society. You can't throw a stone in a crowd of people in the US without at least hitting 20 people who have some sort of ink.
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Another interesting aspect of Black's backstory, although it hasn't been explored yet, is that he's said in NXT that each of his tattoo's is a scar and represents a story from his life. How dark or serious are those stories?
Are they crazy war stories from the battles he's been in or are they cautionary tales to be avoided? If they explore his tattoos and the potentially macabre stories behind them, then WWE could easily add those cryptic meanings to his character along with his foggy entrance to the ring.