In a reference to the Marine's confrontation with the Cyberdemon, when Blazkowicz defeats the "Harbinger of Doom", the creature states that he will return in the future to confront his descendants. In Wolfenstein RPG, it is hinted that the Doom 64 Marine is a descendant of William "B.J." Blazkowicz, to whom the Marine's helmetless look in the original games bears a striking similarity. The Marine in Doom 64 is less muscular, with slightly modified green armor with black highlights, a black helmet with an antenna, and a blue visor.
However, whilst id Software chose a somewhat generic, male pictorial representation of the Marine for the box art, as well as gameplay purposes (damage feedback, story transitions), the true identity of the Doom Marine is meant to be the player themselves and so these depictions should only be considered illustrative. The Marine is often referred to in the fan community as the "Doomguy". The Marine grins upon picking up a new weapon, and the most emotional face is seen when the Marine suffers 20 hit points or more taken away during a single attack, showing a shocked face. When the Marine takes damage, his reaction is a mixture of pain and anger. In Doom, Doom II, and Final Doom, the Marine expresses little emotion at the horror unfolding around him, maintaining a stern and alert glare, eyes constantly darting left and right. The Marine appears without a helmet in the cover art of Doom II and in the ending to The Ultimate Doom episode IV, "Thy Flesh Consumed". This image, with the addition of a shotgun, clutched in his left hand, is carried over to the introduction screen of Doom. The Marine is firing a machine gun that doesn't make an appearance in the final game and fighting a CyberDemon. In multiplayer mode and in the ending of Doom II: Hell on Earth, the player's in-game avatar is based on this depiction, wearing green, red, brown and indigo. In single-player mode, the Marine wears green armor and a light grey space helmet that conceals his facial features. His face is seen in the game's HUD, where it is shown as a Caucasian male with light brown hair, a buzz cut, and blue eyes. On the box art for the original Doom, the Marine is portrayed as a muscular man standing 6 ft 2 in (188 cm) tall and weighing 230 pounds (104 kg). Later, when asked, Tom Hall and John Romero confirmed that the Marine was, at least originally, a descendant of B.J. In the finished product, this nearly happens to the Marine in the final level of the first episode, but the player survives. "Dacote" is an acronym for "Dies at conclusion of this episode", and Buddy was supposed to be killed by a boss at the end of the planned third episode. The sole non-playable character, Buddy Dacote, bore the most similarities to the original game's eventual protagonist. Tom Hall's original design draft, "The Doom Bible", described several planned characters, all of whom went unused in the final version. In 2021, According to Doom Eternal's director, Hugo Martin that the female Doomguy was nearly added, but scrapped due to how much of an endeavor it would have been. In 2020, id Software co-founder, John Romero revealed that the real name of the character is Doomguy. In 2017, Romero stated that he was the original model of the character for the cover box art. John Romero's original sketch and model of Doomguy was made on clay. Romero described this choice as increasing player immersion: "There was never a name for the marine because it's supposed to be YOU ". The Marine is not referred to by name in the original game. He received mainly positive reviews, with some critics praising him as the Doom series' badass and violent protagonist.
He has featured in several other game franchises, including his likeness as a customizable skin for the Mii Gunner character in Super Smash Bros. He has appeared in several other games developed by id Software, including Quake Champions and Quake III Arena. In Doom Eternal, he is voiced by American voice actor Matthew Waterson, while Jason Kelley voices the character in that game's downloadable content The Ancient Gods: Part Two. Within the Doom series, Doomguy is a space marine dressed in green combat armor who rarely speaks onscreen, and his personality and backstory was intentionally vague to reinforce his role as a player avatar. He was introduced as the player character in the original 1993 video game Doom. He was created by American video game designer John Romero. Doomguy, also referred to as the Doom Marine, the Doom Slayer or just the Slayer, is a fictional character from the Doom video game franchise of first-person shooters created by id Software.