Doomguy

"YOU ARE HUGE! THAT MEANS YOU HAVE HUGE GUTS! RIP AND TEAR!"

-- Doomguy, facing a Cyberdemon in the DOOM comic.

Doomguy is the protagonist of the DOOM series, and the representative of the DOOM series in id Software's extended universe. The UAC in the Reboot Timeline refer to him as the DOOM Marine, the Argenta refer to him as the Great Slayer, and the forces of hell know him as the DOOM Slayer. His previous retconned real names were Flynn Taggart in the Novels, and William Joseph Blazkowicz III. He has no real name as of the reboot series and his identity is intended to be up to the player's interpretation. Throughout the series, he is silent with the exception of grunts of pain, dialogue throughout the DOOM Comic, and two lines of dialogue in DOOM Eternal.

He belongs to the Blazkowicz Family, and is the great grandson of the WWII hero William Joesph Blazkowicz. He is also the son of the scientist and genius Commander Keen. In DOOM Eternal the further details given is that he is, in fact, a male human with an AB+ blood type.

Prior to Classic DOOM
Before Ultimate DOOM in the Original id Timeline, Doomguy enlisted in the United States Space Marine Corps and was trained by Crash. After completion of his training, he was stationed on Earth. Outside of his military activities, he kept a pet rabbit named Daisy. The only known incident from his time with the USSMC was a superior officer ordering him and his squad to fire upon unarmed protestors, and a conflict between Doomguy and his commanding officer escalated to Doomguy assaulting him. As a result, a court martial sentenced him to serve on Mars with the UAC as punishment. Daisy was left behind on Earth, possibly with Keen.

Classic DOOM (Ultimate DOOM, DOOM II, Final DOOM)
In Classic DOOM, Doomguy is depicted as a muscular space marine wearing green armor with exposed arms, and his ab plate torn open, quite possibly due to the claws of the Demons. His face is shown in the status bar and the ending screen for Thy Flesh Consumed, and the back of his head is shown in the box art for DOOM II. He has dirty blonde hair and sports an unusual buzzcut with zig-zags on the back of his head.

In the first known incident of a Hell Invasion upon a human realm, the UAC accidentally opened a portal in their bases of Phobos and Deimos, and Doomguy and his squad were sent to investigate the Phobos base. Doomguy was left to secure the parameter of the Hangar, while the rest of the squad went in. After hearing their deaths over his comm unit, he decides to enter the base alone. He fought through the Phobos base eventually reaching the teleporter, the Phobos Anomaly. After stepping through the teleporter, he is torn apart by various demons waiting on the other side, and he is sent to Deimos, which has been annexed by Hell. Now Undead, Doomguy fights through the subverted Deimos base, while the Cyberdemon has his minions construct the Tower of Babel. When Doomguy reaches the Tower of Babel, he has a battle with the first Cyberdemon. After emerging victorious, he looks over the edge of Deimos to discover that he is in Hell. He rappels down to the Hell Keep, and fights through the various Hellish locations, eventually reaching the capital of Hell, Dis. He fights the Spider Mastermind, the leader of the invasion, and defeats her. Hell opens a gateway to Earth for Doomguy, which he walks through to discover a burning City, with Daisy decapitated and put on a stake. Enraged, he enters the burning city, and fights his way through to another Spider Mastermind, and quickly dispatches her. When stepping through the gateway, the Icon of Sin directly interferes, sending him to Hell once again, in SIGIL. Doomguy smashes through the base to find both a Spider Mastermind, and a Cyberdemon. Killing them both, he steps through the final gateway to emerge back to Earth.

Back on Earth, he encounters several refugees being attacked by a Zombieman, he kills the Zombieman, then proceeds to join a squad of USSMC Marines, they fight the Demons, however, all of the Marines end up dying. Alone, Doomguy proceeds to the Entryway of the Starport. Learning of the plan of the Wise Men of Earth to fly the remaining population away from Earth using the remaining ships, he resolves to lift the flame barrier from the Starport. In the Circle of Death, he opens the imprisoned human population and opens the barrier, allowing Earth's population to escape to the stars. Mission Control in space informs him that the portal on Earth is in Gotcha!, located in the center of Mesquite, Texas. When arriving there, he sees no way to close the portal from Earth's side, so decides to jump through and ends up in Nirvana. Fighting through Hell, he reaches the lair of the Icon of Sin, and the two battle for the first time. After firing three rockets into the Icon of Sin's exposed brain, the Icon of Sin dies, and Earth begins reconstructing.

In TNT Evilution, Doomguy was in command of the armies of the Io UAC base. While a large demonic ship was sending legions of Demons onto the surface of Io, Doomguy was on a lunar walk. When returning to the base, he encountered an Imp and realized what had just occurred on the base. He chooses to battle through Io Labs and the Io Military Base. Fighting into the night, he arrives at Central Processing where the gate was located. Jumping into the gate, he fights his way through hell, and encounters the Demon-Spitter at Last Call. Killing the Demon-Spitter, he emerges from Hell after having a temporary truce with Hell.

In The Plutonia Experiment, Doomguy is on the beach when he receives the call that an Earth Base where the Quantum Accelerators are being tested is under attack. Arriving there alone, he realizes that by the time that USSMC reinforcements arrive, it will be too late. Entering the compound alone, he arrives at Hunted, where he destroys the first Prototype Quantum Accelerator. Being sent to Hell in the process, he fights his way to the Devil Hive. Encountering the Gatekeeper and subsequently killing him, the final Prototype Accelerator is destroyed, and Doomguy is sent back to the Human Realm.

DOOM 64
Suffering from PTSD, Doomguy is discharged from the USSMC. They offer him mental treatment with their doctors, which don't help his mental state. The UAC, meanwhile receives signals from the abandoned Phobos base, indicating that a demon escaped Doomguy's grasp and resurrected many of the dead demons, as well as reopening a previously closed gate. Combined with mutations from the massive radiation being enforced on the base as quarantine, it creates a threat large enough to warrant a military response. The decision was that since Doomguy is the only experienced military survivor of the Hell Invasions, he will be sent with upgraded equipment to finally stop the remaining Hellish forces. Going through the abandoned Phobos Base, while finding one of the Demon Keys and an Unmaker, he reaches the Final Outpost where the reopened gate is located. Going to the other side once again, he goes through Hell, collects the two remaining Demon Keys, and reaches The Absolution. He closes the three Demon Gates with the Demon Keys, and then takes on the Mother Demon. Killing the Mother Demon, he makes the decision to remain in Hell so that no Demon may ever rise to attack a Human Realm again. However, the Sister Resurrector, angry with the death of the Mother Demon, takes the Demon Keys and his inventory and hides it in her lair, and sends Doomguy back to a UAC base. He fights his way back to Hell, recollects the Demon Keys, and defeats the Sister Resurrector.

Prior to DOOM 3
Sometime prior to DOOM 3, he had already encountered the timeline. Meeting an ancient Martian civilization that would eventually become the Human race of that timeline, a majority of the civilization sacrificed their souls into the Soul Cube, and allowed Doomguy to fight off the invasion. When the invasion was killed off, he soon disappeared, and they honored him by inscribing them into their history, and making a tomb that his body would've gone in to respect him.

DOOM 3
During Doomguy's travels across dimensions, he takes the role of a corporal marine transfer headed to the UAC Base on Mars, and it seems by fate he was destined to fight the Hell Invasion in this realm. He arrives on the base directly prior to the Invasion. In this universe, the UAC is heavily corrupted by Malcolm Betruger, who opens the gate in exchange for being transformed into the Maledict. Doomguy not yet encountering Betruger, is ordered by Sargent Kelly to find a missing scientist. He goes and finds him at the old Communications Facility, only for the gate to be opened and the scientist to be possessed. Killing the scientist, Sargent Kelly orders Doomguy to regroup with any remaining Marines. When most Marine groups are killed off, Kelly narrows it down to Bravo Team, as they are the only remaining Marines to carry a distress transmission card. After Bravo Team falls, he continues and finds a survivor that gives him the transmissions card. Doomguy continues to the Communications Facility where Campbell and Swann destroy the console, Doomguy instead heads to the top under orders of Sarge to manually send the transmission via the satellite. When Swann directs Doomguy to not send the transmission, Doomguy cancels it in order to prevent the fleets from reaching Mars, and the Demons getting on the ships and going back to Earth. Betruger then finally notices Doomguy, and attempts to halt his progress and threatens to send the transmission himself. Doomguy fights his way through the Enpro Facility and prevents a gas leak from killing him. He then goes to the Delta Labs, where Sarge contacts him to direct him through the Delta Labs. Doomguy continues through the Delta Labs where he meets Ian Mccormick, who sends him through the teleporter to the next part of the Delta Labs. Doomguy continues and finally meets Betruger, who sends two Hell Knights on him, and then overloads the teleporter so that he is forcefully sent through. He makes his way through Hell and encounters the Guardian, who holds the Soul Cube. When Doomguy kills the Guardian, he acquires the Soul Cube, and is sent back to the Mortal Realm. He continues through the base and encounters Swann, who tells him that Sarge has been corrupted under the influence of Hell and Campbell has gone after him. When Doomguy arrives at the CPU Complex, he finds Campbell mortally wounded, and Campbell tells him that Sarge has taken his BFG 9000. Doomguy, while being telepathically taunted by him, hunts Sarge down. He fights and kills Sarge at the CPU Banks and takes his BFG 9000, and continues to Site 3. As the subversion becomes more extreme, he reaches Site 3 where ancient structures are housed, and the Tomb of the Hero is located. Eventually, he reaches the Hell Hole, the natural Hell portal embedded in Mars guarded by the Cyberdemon. He kills the Cyberdemon and is found and rescued by an investigation fleet. It is assumed shortly after this he once again traveled through dimensions to continue his crusade.