After the bullshit ending of DOOM 2016, the Doom Slayer gets transported to the Overwatch Version of Earth. Contrary to popular belief, Doomguy/Doom Slayer is the most light-hearted and possibly insane person anyone could ever talk to or get acquainted with. Unfortunately for Overwatch, they'll have to do the latter. Maybe they can teach him to use his brain?

Hell no longer could Deal with the Doomslayer. He was too much. They also feared killing him as to be trapped with his soul. So they sent him away. A drift in the stars for hundreds of years till eventually he was discovered by Infinity.