adjutant reflex was mentioned in the universe post canon fodder array with words.
if you don’t know the name he was part of a halo 3 viral marketing campaign iris here’s a link about him
Adjutant Reflex, as far as I am aware, does not actually exist within Halo canon. He was constructed by Bungie employees masquerading as a Forerunner intelligence from the future to give Halo 3 a ‘larger than life’ feel to it. A lot of people thought it was cool. I, personally, found it to be quite irritating and no more than a few guys taking Halo a bit too seriously. A ‘troll’ if you will (the only difference being that he was a Bungie employee that had way too much time and community endorsement on his hands).
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> Adjutant Reflex, as far as I am aware, does not actually exist within Halo canon. He was constructed by Bungie employees masquerading as a Forerunner intelligence from the future to give Halo 3 a ‘larger than life’ feel to it. A lot of people thought it was cool. I, personally, found it to be quite irritating and no more than a few guys taking Halo a bit too seriously. A ‘troll’ if you will (the only difference being that he was a Bungie employee that had way too much time and community endorsement on his hands).
I am almost positive that AR is canon. 
I always thought it was a really cool idea, though I was not around for him, unfortunately. Catalog seems to be the new version of AR.