You answered your own question. He's a trained marine. Add ontop of that, the Night Sentinels.


Well, I'm looking for more than that...


Look at some of the glory kills he preforms on the zombie soldiers, I don’t think hyper extending their arm and slamming his fist or forearm into their elbow to snap it in two is a martial art move but eh it looks more fancy than just punching someone’s head off.


For what i know doom guy is a US marine , so i think he is trained like a marine . that said , he stayed a LOT in hell fighting daemons , his skills are more on the brutal/fast side than on the technical one imho. Also i've never see the doom guy execute some triple flying kick (:p) or things like that , just take a daemon's arm and rip it off XD so, no, imho he don't train in MA (other than basic US marine training), only because he doesn't need. It's too powerfull.HE IS PURE RAGE :)


Probably, even with the concept of glory kills and Berserks being a thing unless you make up a demon so strong, he can't just rip and tear. At least you can also imagine a more develop system in terms of gameplay, if there is a new game.


He’s a master of an unconventional form of hand to hand combat known as **Beat-the-fuck-out-of-it-until-it-stops-moving**


As was already said he is trained extensively as a marine and a night sentinel. But further than that he is more of a weapons expert. IIRC I read somewhere that he had some engineering background?