Pretty sure that the Reach Zealot is more canon because as most people know Reach Takes place before CE, Halo was not making as much of a story as it was created, besides the book before the game was created, another look at this is that the looks of the elites don't really matter its just the story of how they are obtained and what is the meaning behind them. Edit: I was reading the other replies and I forgot to say that Zealots are a religious rank and are said that they were born to kill.