They look so damn similar, from the style and color of their armor down to their behavioral traits. Seems like Bungie simply saw the success that Doom had over their Marathon series and thought to themselves “you know what our next game needs? A massively overpowered super soldier in green high tech armor who spouts sarcastic one liners in the face of an overwhelming alien invasion” and went to town with that concept. And it worked like a charm, they cranked out six massively successful games before id/Bethesda decided it was time to reboot the Doom franchise 2016.
Perhaps it was payback for them to give Doomguy the Crucible in the reboot games (which looks a lot like the energy sword from Halo), but I can’t help but think these two are essentially the same character.
Possible, but in that case it might have actually helped them to first tie them up in a difficult and potentially expensive lawsuit in order to lower the purchase price. Sounds like something Microsoft would do…