Here's the characters of the classic ''Doom'' series: specifically, the original ''VideoGame/{{Doom}}'', ''VideoGame/DoomII'', and ''VideoGame/Doom64''.

For other characters and bosses in ''VideoGame/Doom3'', see Characters/Doom3.

For the characters and bosses in ''VideoGame/Doom2016'' and its sequel ''VideoGame/DoomEternal'', see Characters/Doom2016.

[[foldercontrol]]

!The Marine and his companion
[[folder:The Doomguy]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/doomguy_face_sprite.png]]
[[caption-width-right:230:[[labelnote:Click here for his full body in ''Doom I'' and ''Doom II'']] https://static.tvtropes.org/pmwiki/pub/images/doomguytransparent.png[[/labelnote]]]]
[[caption-width-right:230:[[labelnote:Click here for his full body in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/doomguy64transparent.png[[/labelnote]]]]
->''"You're a marine, one of Earth's toughest, hardened in combat and trained for action."''
-->-- Excerpt of ''The Story So Far'' section of the ''Doom'' instruction manual
\\
The PlayerCharacter.\\
\\
In the original ''Videogame/{{Doom}}'', he's a nameless space marine sent to do grunt work on Mars after an incident over not wanting to kill innocent people on Earth causes him to lash out against his commanding officer and [[NoHoldsBarredBeatdown put the bastard in a full-body cast]]. During his [[NothingExcitingEverHappensHere dull-as-dirt assignment]], it seems the scientists of the Union Aerospace Corporation (UAC) are conducting experiments with teleporters when everything falls to pieces. One of Mars' moons and a UAC outpost, Deimos, completely vanishes into the ether while another, Phobos, is immediately overrun by TheLegionsOfHell. Everyone is either slaughtered or converted into minions of the invaders. The marine dispatches to Phobos, where he proceeds to clean up the situation as brutal and efficient as possible. During his one-man war against the forces of Hell, he discovers what became of Deimos (ended up floating above Hell itself) and then treks down to the surface of Hell to finish the job.\\
\\
When the sequel ''VideoGame/DoomII: Hell on Earth'' rolls around, the marine had just finished ripping Hell a new one when a distress signal alerts him that the armies that invaded the Mars moon bases have now breached their way to Earth. The humans who are able to escape the genocide decide their only recourse is to escape the planet, but their exit route is barricaded by the invaders and obstructed by a force field they set up. The marine is called to break the line of defense and deactivate the force field on behalf of the other humans so they may escape, which he does and remains as the last human on Earth. However, further communication from the escaped humans reveals that the epicenter of the invasion is on Earth and nearby to the starport, allowing the marine to finally push back against the invaders. After fighting their forces he decides to cross back into Hell yet again, this time with the intent of making sure they can never invade anywhere ever again. After this trek through Hell, he manages to essentially ''destroy'' it, literally leaving no place for the damned to go once they die.\\
\\
In ''VideoGame/Doom64'', the marine is pulled back into service when demons start to reappear, stronger than ever, on the old moon bases. Figuring that only he has the expertise to deal with this threat, he is once more sent into the fray to slaughter said demons (which he does with gusto), deciding once the job is finished to remain in hell and make sure the demons never attempt an invasion again.

\\
For the tropes pertaining to the Doom Slayer of the [[VideoGame/Doom2016 reboot continuity]], see [[Characters/Doom2016TheDoomSlayer that character page]].
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* ActionHero: The Doomguy is a straight-up balls-to-the-walls killing machine who slaughters his way through the forces of Hell without qualm or respite.
* AmbiguouslyHuman: Starting off just fine, the Doomguy did canonically die at the end of the first episode of the original. This only effectively displaced and inconvenienced him however, sending him to the hell-bound Deimos base where Episode 2 is set. Since then he's returned from Hell as well as dived right back into it multiple times over, so it's not entirely clear whether he's really human or truly alive by our standards anymore.
* AxCrazy: A heroic example. While there's no doubt he's a good guy, the fact that he kills his enemies with too much joy makes clear he's not exactly well lit.
* BadassFamily: Doomguy has been confirmed (at least in the classic continuity) to be the son of Billy Blaze (A.K.A. VideoGame/CommanderKeen, William J. Blazkowicz II) and great-grandson of [[VideoGame/{{Wolfenstein}} William J. Blazkowicz]].
* TheBerserker: He wipes out entire armies of demons with unimaginable ferocity. Taken up to 11 with the Berserker powerup, where he starts one-shotting demons with his bare fists.
* {{BFG}}: He wields [[TropeNamer the very first]] Big Fucking Gun.
* BloodKnight: He smiles sadistically every time he obtains a new weapon and grits his teeth when he fires with it. And after his initial confrontation with Hell, it's implied that everything afterwards through ''Thy Flesh Consumed'' and ''II'' weren't just to save humanity, but because his sanity plunged [[AxCrazy so low]] that he pursued more slaughter and gibbitude on everything demonic, though Daisy dying [[RoaringRampageOfRevenge didn't help that.]]
* BruiserWithASoftCenter:
** Doomguy had a pet rabbit named Daisy (the past tense usage there being the [[RoaringRampageOfRevenge biggest regret of the forces of hell by far]]).
** Doomguy was also only sent to Mars in the first place because he assaulted his superior officer who ordered him to fire on civilians. This being Doomguy, the "soft center" still involved putting someone in a body cast.
* BulletproofVest: His IconicOutfit includes a green vest that, according to the manuals, is kevlar.
* CanonName: Somewhat, as several different sources give him several different names: in the novels based on the original games, he is named Flynn "Fly" Taggert, the ''Doom 3'' novels name him John Kane, and in the mobile RPG he's Stan Blazkowicz. Moreover, they're only "somewhat" canon in that, no matter how many sources try to attach a name to him, the people from id Software who made the game continue to insist the Doomguy ''doesn't'' have an official name, since giving him one would get in the way of his status as a cipher for the player - i.e. he doesn't have a name because he's just supposed to be ''you'', albeit you as a SpaceMarine who can go toe-to-toe with Hellspawn.
* CantBatheWithoutAWeapon: In the first ''Doom'' novel, he decides to risk [[ShowerScene taking a shower]] in the Phobos Lab infirmary. He takes the trouble to lock the doors and turn off the lights except for the one in the shower stall and keeps his trusty shotgun within arm's reach in case of he's attacked. Luckily he doesn't. [[spoiler:He gets attacked ''immediately'' after leaving the infirmary though.]]
* CelibateHero: The Doomguy never expresses any interest in sex or romance throughout the series. His chastity may be for religious reasons, as he is a devout Catholic.
* CharlesAtlasSuperpower: There's technically nothing supernatural behind his Berserk Punch and ability to withstand direct hits from a rocket launcher, at least in the pre-2016 games.
* CulturedBadass: If his description in the ''Quake III Arena'' manual is to be believed, Doomguy has brains in addition to brawn.
-->''Distracted and intelligent sounding, (but not a member of the intelligentsia, more like a well-educated tradesman) this guy may be a few cards short of a full deck, but his training serves him well. He's a bad-ass in the arenas.''
* {{Determinator}}: He will ''never'' stop, until he has crippled the dominions and powers of Hell, leveling it totally, [[DependingOnTheWriter or turning the ruin into his kingdom to rule over alone]]. The demons hate and fear this aspect of his character above all. [[spoiler:And it turns out that this insane level of determination carried him all the way through the rebooted series!]]
* DidYouJustPunchOutCthulhu: He's taken on demonic horrors that would have made even Jesus wet his pants and busted a cap in the ass of each one of them.
* DoomedHometown: Doomguy's hometown on Earth is attacked in ''Doom II: Hell on Earth'', and is the location of a portal to Hell that he must go through to stop the invasion.
* EmpoweredBadassNormal: The Doomguy is pretty much just a soldier armed with two things: an arsenal full of really big guns, and a bottomless hatred for the LegionsOfHell. However, he can also temporarily empower himself with hell artifacts that grant him power-ups such as temporary invulnerability or invisibility. The berserk pack makes him strong enough to punch demons into paste. But even without these things, he's still able to go up against every demon in Hell and come out on top.
* {{Expy}}: He bears a strong resemblance to B.J. Blazkowicz, the player character of ''VideoGame/Wolfenstein3D'', and fills the same role.
* FlatCharacter: A deliberate example, as the devs wanted players to project their own personality onto him. Between all his appearances, though, he does display a consistent but distinctly uncomplicated personality, and it can be summed up with just two words: [[TheBerserker Rip, and Tear]].
* FromNobodyToNightmare: From the demon's perspective he is the embodiment of this trope. [[LeeroyJenkins Running and gunning]] into their midst, just another mortal, a marine, a grunt to either slaughter or zombify. But then he ends up becoming a [[{{Determinator}} serious threat they can't silence]], and goes on to destroy the forces of Hell ''several times over''. Understandably, he is very much now TheDreaded in Hell.
* GlassCannon: While he can hit demons hard with his arsenal and actually has decent health, Doomguy loses it as fast as them if he doesn't dodge their attacks quickly.
* GoodOldFisticuffs: One of Doomguy's "weapons" is a basic punching attack. It functions as a JokeWeapon for the most part. That is unless you grab a Berserk Pack, which turns it into a LethalJokeWeapon against the weaker monsters.
* GoOutWithASmile: The second intermission in ''Doom II'' has Doomguy secure humanity's continued survival by enabling their evacuation off-world. Surrounded by demons, the narration describes that he's content with [[HeroicSacrifice dying alone to the hordes of hell]]... and then he receives a message from the fleet that [[EarnYourHappyEnding there is a possibility to end the demonic invasion]], motivating him to [[SubvertedTrope walk off his wounds and continue the fight]].
* GuestFighter:
** Doomguy is a secret character in the PC version of ''VideoGame/TonyHawksProSkater 3'', due to Gearbox Software being the one who ported the Windows version of the game.
** Doomguy appeared as a playable character in ''VideoGame/QuakeIIIArena'' where he was simply named "Doom".
* HelmetsAreHardlyHeroic: The boxart for ''Doom II'' shows him having ditched a helmet as he takes on a Cyberdemon. Otherwise averted, as the first game's art and in-game sprites of all games show that Doomguy is wearing a helmet.
* HeroicAmbidexterity: While Classic Doomguy wields two-handed guns with his right hand at the trigger, he punches and uses his pistol southpaw.
* HeroicComedicSociopath: His incarnation in the comic book. [[LargeHam It has to be seen to be believed.]]
* HeroicLineage: His father [[VideoGame/CommanderKeen saved the world from aliens]], and his great-grandfather [[VideoGame/{{Wolfenstein}} fought]] [[ThoseWackyNazis Nazis]].
* HeroicMime: Never speaks beyond VoiceGrunting in the first three games.
* HeroicSacrifice: Seemingly dies in one at the end of ''64'' , as he decides to stay in hell to fight its forces for as long as he can. [[spoiler:It didn't take, as he went on to become the Doomslayer after an encounter with the Maykrs.]]
* HisNameReallyISBarkeep: WordOfGod [[https://twitter.com/romero/status/1314667748769910784?s=20 proclaims that Doom Guy is his real name.]]
* HyperspaceArsenal: Carries a huge arsenal of weapons in all games. Common to all are a pistol, a shotgun, a chaingun, a rocket launcher, a plasma gun, and the BFG-9000. He adds more to this depending on the game. It's a wonder he doesn't clank when he walks.
** ''Doom II'' adds the double-barrel "super" shotgun.
** ''Doom 64'', in addition to its own version of the double-barrel shotgun, adds the Unmaker.
* IChooseToStay: At the end of ''Doom 64'', Doomguy decides to stay behind in Hell to make sure he's killed off the demons for good.
* ItsPersonal: In the classic game, they killed Daisy, butchered all his buddies on Mars, and then invaded Earth.
* LanternJawOfJustice: If the status screen is to be believed.
* LateToTheParty: Doomguy's many incarnations are always too late to save any survivors after Hell initially attacks Mars.
* LightningBruiser: Classic Doomguy becomes the "hard-hitting speedster" version of this in ''Doom II''; the original game had its moments of comparative "breather" time, but ''II'' was where the lightning-fast array of flying bullets and hellfire and the emphasis on constant movement that has become definitive of the series was really introduced. He can also play this trope straighter if he finds ways to upscale his health and armor, which give them protection without impacting his movements or firepower.
* NoNameGiven: While he has plenty of fanon names (and a couple arguably canonical), the Doomguy really has no official, cemented name. Romero stated that he wanted the players to feel like ''they'' were the marine and to invent their own personality.
* OneManArmy: It's this guy and every demon that the depths of Hell can throw at him. The demons are rightly terrified of him. According to [[https://www.doomworld.com/forum/topic/85657-doomguys-total-kill-count/ this post]] there are 8265 demons in just the first two games. And even considering most players won't kill every single monster, it will still probably be more than half that by the end.
* OneRiotOneRanger: By the time the Mother Demon of ''Doom 64'' starts causing more problems, he's proven himself good enough at killing demons that he's the first and only person sent to deal with it.
* PaletteSwap: In multiplayer other marines become this.
* {{Patricide}}: In a bonus level of ''Doom II'', he is forced to kill four clones of his own father, Billy Blaze, in order to leave.
* PsychoForHire: Maybe. He's a marine who enjoys slaugthering demons. A rare benign version, though.
* RealMenLoveJesus: In the novelization, he's a devout Catholic. He probably takes after [[VideoGame/WolfensteinIITheNewColossus his grandmother]].
* RealMenWearPink: The thing that makes the events of ''The Ultimate Doom'''s Thy Flesh Consumed episode truly personal? The demons killed his pet rabbit, Daisy.
* RightManInTheWrongPlace: He was [[ReassignedToAntarctica assigned to Mars as punishment]] after disobeying an order to fire on civilians. When the forces of Hell invade, he proves to be the only person capable of stopping them.
* RoaringRampageOfRevenge: Doomguy slaughters his way through a huge swath of hell because they killed his rabbit.
* ShellShockedVeteran: According to the ''Doom 64'' manual, Doomguy was left with severe PTSD from his experience in the first two games. Nonetheless, when the forces of Hell rear their head again, he voluntarily jumps back into the fight.
* SkewedPriorities: Doomguy seems more upset about the death of his rabbit than the deaths of his army buddies.
* SealedEvilInADuel: Doomguy at the end of ''Doom 64'' is stated to stay in Hell to ensure the demons never cause trouble again. [[spoiler:As the reboot series suggests, fate had different plans for him.]]
* SirSwearsALot: He'll say some rather ''[[https://doomwiki.org/wiki/Quit_messages#Extras unflattering things]]'' about you, [[TheFourthWallWillNotProtectYou the player]], should you [[ScrewThisImOuttaHere choose to quit]] instead of continuing the campaign against Hell.[[note]]According to Creator/JohnRomero, these were never intended to be seen outside the developer's copies, but somehow made it onto the Shockwave Flash port of the game.[[/note]]
* SlasherSmile: Whenever classic Doomguy picks up a new weapon, he gets a very psychotic grin.
* SociopathicHero: His narrations in the "cutscenes" and instruction manuals give this impression. Classic series only.
* SoleSurvivor: Original Doomguy is the only marine who survived the initial invasion, though humanity as a whole survived, as the sequels reveal.
* SpaceMarine: A non-SuperSoldier example. [[spoiler: However, the Super Soldier aspect does get played straight in the modern games after Samur Maykr puts him through the Divinity Machine, turning him into the Doomslayer (in effect, making the Doom Slayer a demonic version of Captain America).]]
* StrongFamilyResemblance: Doomguy in the original continuity has remarkably similar facial features and body structure to his great-grandfather, B.J. Blazkowicz.
* SuicideMission: One man attempting to fight off an entire army of demons, and in multiple games invading ''Hell itself'' singlehandedly. Nobody's expecting you to come out alive. Zigzagged in all games save for ''ROE'', where it's left ambiguous [[note]]the ending is a fade to black with the scientist's voice contacting the Engineer, but the Engineer shut off life-support in the base to get the power to teleport to Hell[[/note]], in that you complete your mission and live.
* ToHellAndBack:
** In the first game he ends up in Hell after discovering where Deimos had teleported to and wanting to teach the demons a lesson on messing with him. Hell "plays fair" and spits him back out into the human world after his rampage kills the Spiderdemon.
** In the second game, he voluntarily returns to Hell and completely wrecks the joint, to the point that he is left to wonder what would become of the evil people in the world when they die.
** In ''Doom 64'' he kills the Mother Demon and apparently exterminates the demons completely. Also he stays in hell by choice in order to ensure that no further demonic incursions happen.
* UnexplainedRecovery: Despite being mauled by demons at the end of the first episode of the first game, he was somehow able to survive and continue his rampage against the forces of Hell. How this happened is never clearly stated, given the ExcusePlot.
* WouldNotShootACivilian: He may have [[SociopathicHero issues]], but he draws the line here. [[AllThereInTheManual The backstory]] asserts that he was [[ReassignedToAntarctica transferred to Mars]] because, upon being ordered to fire on a group of civvies by his commanding officer, he responded by ''beating the man so hard he got put in a body cast''.
* YoungerThanTheyLook: According to the timeline released by Bethesda, Doomguy's father [[VideoGame/CommanderKeen Billy Blaze]] was born in 1982, and the original ''Doom'' takes place in 2022. This means that Doomguy would have been in his late teens or early twenties when he first fought the legions of Hell.
[[/folder]]

[[folder:Daisy]]
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[[quoteright:129:https://static.tvtropes.org/pmwiki/pub/images/daisyultimatedoom.png]]
[[caption-width-right:129:Daisy in the ending cutscene of ''Doom I'']]
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->''"Besides, someone was gonna pay for what happened to Daisy, your pet rabbit."''
-->-- Excerpt from the ''Thy Flesh Consumed'' ending screen from ''The Ultimate Doom''

Doomguy's pet rabbit, which was only seen in the [=PC=] version's ending screen. She was slaughtered by the demons during their breakout into Earth, and that serves as the catalyst for Doomguy's [[ItsPersonal true enmity with demonkind]].
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* AscendedExtra: In her first appearance, she was just a nameless bunny head impaled on a spike in the endscreen of the first game. The bonus episode "Thy Flesh Consumed", released years later as part of ''The Ultimate Doom'', revealed she was Doomguy's pet and a motivation for his RoaringRampageOfRevenge.
* BadPeopleAbuseAnimals [=/=] KickTheDog: Likely the developer's initial motivation to include a severed rabbit head on a pike, before the memes inspired them [[AscendedMeme to retcon it as Doomguy's pet]].
* {{Biography}}: ''VideoGame/DOOMEternal'' reveals that Doomguy wrote a book about her titled "My Best Friend, Daisy".
* CradleOfLoneliness: Averted. Thanks to the positioning and pixellated artstyle, a common misconception is that Doomguy is holding Daisy's head in the endscreen, when it's actually a wooden pike jutting out from the bottom of the viewable screen. The endscreen of "Thy Flesh Consumed" plays this straight, showing Doomguy carrying Daisy's head with an angry, barely-holding-back-tears expression.
* DecapitationPresentation: Of the pike variety.
* EasterEgg: Daisy is alive and hidden somewhere in every level of ''DOOM Eternal''.
* ImpaledWithExtremePrejudice: She's presented at the end of Episode 3 with her head impaled on a pike.
* ItsPersonal: Implied by the endscreen text.
-->"''Besides, someone was gonna pay for what happened to Daisy, your pet rabbit.''"
* OffWithHisHead: Poor Daisy. The demons even put her head on a spike.
* TragicKeepsake: ''VideoGame/QuakeChampions'' mentions that Doomguy carries around Daisy's rabbit foot as a reminder of what he's fighting for, and even in ''DOOM Eternal'', he still keeps her empty cage in his Fortress of Doom.
[[/folder]]

!Demons
!!Enemies
[[folder:Former Humans (Zombieman, Shotgun Guy, and Heavy Weapon Dude)]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/zombiemantransparent_0.png]]
[[caption-width-right:230:Zombieman in ''Doom I'' and ''Doom II'']]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/formersergeant_sprite.png]]
[[caption-width-right:230:Shotgun Guy in ''Doom I'' and ''Doom II'']]
[[caption-width-right:230:[[labelnote:Click here to see Zombieman and Shotgun Guy in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/shotgunguy64.transparent[[/labelnote]]]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/heavygunner_sprite.png]]
[[caption-width-right:230:Heavy Weapon Dude in ''Doom II'']]
->''"Just a few days ago, you were probably swapping war stories with one of these guys. Now it's time to swap some lead upside their head."''
-->-- Zombiemen's description in the ''Doom'' instruction manual

->''"Same as the Former Humans, but much meaner, and tougher. These walking shotguns provide you with a few extra holes if you're not careful!"''
-->-- Shotgun Guy's description in the ''Doom'' instruction manual

->''"Geeze, weren't shotgun zombies bad enough? At least when you fade these jerks you get a cool chaingun."''
-->-- Heavy Weapons Dude's description in the ''Doom II'' instruction manual

These were the soldiers on Mars (and then Earth) who were "conscripted" into the armies of Hell as front line defenders. They are essentially zombies and increase progressively in toughness (Grunts go down in a few shots while Commandos are armed with a chaingun and will take some punishment). Classic series only.
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* BaldOfEvil: The Sergeants and Commandos are evil zombies that lack hair.
* TheBrute: The Commandos, or Heavy Weapon Dudes, while not freakishly huge, are noticeably larger than their zombie brethren.
* EliteMooks: Heavy Weapon Dudes' slightly better resistance and more efficient weapon make them more dangerous than Zombiemen and Sergeants.
* EmptyShell: Implied to just be walking corpses with none of the original "owner's" personality or memories, as evidenced by their monstrous growling and lack of any coherent speech.
* EverythingsDeaderWithZombies: They're former {{Space Marine}}s killed and animated (or possibly possessed) by demons. In combat, they're very different from what you would expect from a zombie though; most notably, they set themselves apart from Hellish creatures by using hitscan firearms.
* FallenHero: A literal example. They started out as other marines but then died (i.e fell) and became zombies.
* GatlingGood: Former Commando's favored weapon. It's quite inaccurate compared to yours, but at point blank it can shred you before you have the chance to turn around.
* GlassCannon:
** While Sergeants are not much tougher than a Grunt and go down easy, their shotguns do pack quite a punch. If they're in large groups, if you have no armor, or if you're in close quarters (or worse, all three) then they can really put a big hurt on you.
** Former Commandos' rapid firing of their weapons makes them one of the most powerful {{Mook}}s. This is counterbalanced by their low HP (70, slightly higher than an Imp's 60) and the ease of making them infight because of the constant firing of their gun and ability to hurt other Commandos.
* TheGoomba: The Grunt and the Shotgun Guy are the most common enemies you'll face, especially in the early levels. The former is this especially, for having the lowest damage per attack and lowest health out of any monster in the game.
* HelpfulMook: Sort of. All former human enemies drop ammo/weapons when you kill them. The Grunts drop clips (ammo for the pistol or chaingun) while the Sergeants and Commandos drop shotguns and chainguns, respectively.
* {{Hitscan}}: The only enemies besides the Spider Mastermind with hitscan weapons, which can make them (Commandos in particular) very annoying to deal with. Mostly balanced by having every zombie-type enemy be heavily inaccurate, but this is only a limit for regular grunts- commandos and sergeants fire much more lead at you, giving them a better chance to hit.
* ImAHumanitarian: ''TNT: Evilution''[='s=] Map 2, "Human BBQ", has a lone Sergeant joining in the group of Imps around the titular human BBQ. The manual from ''Doom II'' is more explicit, and confirms that former humans eat the flesh from the humans they kill.
* ImperialStormTrooperMarksmanshipAcademy: The standard, green-haired zombie Grunts are the most inaccurate with their guns, despite using a hitscan attack. However, this is somewhat averted if you play on the "Nightmare" setting, where all enemies attack relentlessly (which makes them ''more likely'' to hit you).
* ItCanThink: Downplayed: They retain just enough intelligence to operate their guns, but their marksmanship and tactics are pretty poor.
* IHaveManyNames: The names for these enemies are somewhat inconsistent. The names from the start of this section and the image captions are taken directly from the ending sequence of ''Doom II'', but they have others besides that:
** The Zombieman is also called Former Human, Former Soldier, or Trooper depending on which instruction manual you're looking at.
** The Shotgun Guy is also known as Former Human Sergeant or just Sergeant. Players often call them "Shotgunners".
** The Heavy Weapon Dude is called a Former Commando in the ''Doom II'' manual, and in some others is called the Chain Gunner. Players near-ubiquitously favor the latter.
* LittleUselessGun: The guns carried by the grunts look like an M16 rifle, but fire pistol ammo, suggesting that they could be the [[https://en.wikipedia.org/wiki/Colt_9mm_SMG Colt Model 635 SMG]]. They fire very slowly, and their shots do the same damage as the player's pistol. Understandably, Doomguy can't pick these guns up (nor would he want to).
* MadeOfPlasticine: The zombies can ''very'' easily be [[LudicrousGibs splattered]] by heavy weapons like the BFG, Plasma Gun, Rocket Launcher, or an exploding barrel. Amusingly, the green haired grunts in particular can be splattered by Doomguy's Berserk Fist attack or even a stray fireball from a Baron of Hell.
* MoreDakka: Heavy Weapon Dudes (Former Commandos) are NOT to be taken lightly, especially in close-quarters. They fire their chainguns extremely quickly, which can dish out plenty of damage if you're close enough for a significant amount of the bullets to hit.
* PaletteSwap: Surprisingly enough, all three of them are, with the Zombieman and Shotgun Guys being pretty straightforward retextures, and the Commando being much the same, but stretched horizontally to look larger. All three wear the same type of combat armor as Doomguy, only in different colors (tan, black, and red as opposed to Doomguy's green).
* OurZombiesAreDifferent: While they are very much zombies, they differ from traditional depictions by utilizing firearms, lacking any particular desire for human flesh, and for being the result of demonic forces, rather than any disease or virus.
* RedEyesTakeWarning: All variations have red eyes.
* ScaryBlackMan: The Commando has noticeably darker skin than the other zombie types, and of them all is easily the most powerful.
* ShotgunsAreJustBetter: The Sergeant's weapon of choice, to the point his name in the source code is "Shotgun Guy".
* TechnicallyLivingZombie: They're called "zombies" but if you want to dot the "I"s and cross the "T"s they're not actually TheUndead but victims of DemonicPossession.
* ZergRush: Certain later levels in some map packs (''TNT: Evilution'' is infamous for this) have them reappear in massive numbers - Map 09 of ''Evilution'' pits you against hordes of shotgun guys, chaingun guys, and even at the very beginning you are surrounded by a mass of grunts firing upon you from fortifications. If you don't get out of that room IMMEDIATELY, they will quickly tear you apart, even if individually they are inaccurate; there are just so many shots being taken at you.
[[/folder]]

[[folder:Imp and Nightmare Imp]]
[[quoteright:200:https://static.tvtropes.org/pmwiki/pub/images/imptransparent.png]]
[[caption-width-right:200:Imp in ''Doom I'' and ''Doom II'']]
[[caption-width-right:200:[[labelnote:Click here to see Imp in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/imp64transparent.png[[/labelnote]]]]
[[caption-width-right:200:[[labelnote:Click here to see Nightmare Imp in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/nightmareimp_sprite.png[[/labelnote]]]]
->''"You thought an imp was a cute little dude in a red suit with a pitchfork. Where did these brown bastards come from? They heave balls o' fire down your throat and take several bullets to die. It's time to find a weapon better than that pistol if you're going to face more than one of these S.O.B.s."''
-->-- The Imp's description in the ''Doom'' instruction manual

Hell's own soldiers. Brown spiked monsters who are capable of throwing fireballs, Imps are the lowest level of demon that lead the charge for the forces that follow.
----
* CallAPegasusAHippogriff: [[LampshadeHanging As the manual points out]], the "imps" in this game don't look much like the "cute little dude in a red suit with a pitchfork" image that word normally brings to mind, being instead brown humanoid monsters covered in spikes and throwing fireballs.
* DoingInTheWizard: In the novels their fireballs are explained as the imps spitting up globs of a chemical that reacts with oxygen to ignite, which the imps then fling like baseballs of flaming snot.
* EliteMooks: Nightmare Imps acts like their regular counterpart would in Nightmare mode: they move twice as fast, and their faster and stronger fire power makes them very dangerous.
* {{Fireballs}}: Their primary ranged weapon.
* GlassCannon:
** On Nightmare (and Ultra-Violence + in the Unity port), Imps compensate their vulnerability by the speed they throw fireballs at you.
** In ''Doom 64'' Nightmare Imps throw fireballs twice as fast as regular Imps do, but they are not more resistant.
* TheGoomba: Your first properly demonic enemy that you encounter, and one you'll see throughout the games. Defensively, they are a bit of a step up from zombies -- in [=MAP01=] of ''Doom II'' for example, you will be solely armed with your pistol until late in the map, and firing 5-15 damage bullets versus 60 HP Imps takes quite a bit more to kill them, compared to the 20-HP zombie grunts. Offensively, their fireballs are slightly stronger than Zombiemen's pistol or Sergeants' shotgun, but are also way easier to avoid.
* ImAHumanitarian:
** Implied in map 21 of ''Doom II'', "Nirvana", which opens on a group of Imps clustered around a mutilated human corpse.
** Much more strongly implied in map 2 of ''TNT: Evilution'', "Human BBQ", which loads into a group of four Imps standing around the titular human barbeque.
* LeanAndMean: ''Doom 64'' gives Imps a leaner design to make them look more vicious, and Nightmare Imps are even viler.
* MadeOfPlasticine: Being [[HumanoidAbomination humanoid monsters]], the Imps and Nightmare Imps can also be [[LudicrousGibs splattered]] by heavy weaponry and ordinance just like the former humans. And, just as amusingly, this can be done with Doomguy's Berserk Fist attack as well.
* {{Mooks}}: Hell seems to have a nigh-unlimited supply of Imps; expect to see them more than every other Demon combined.
* MovesetClone: Nightmare Imps have the same fireball attack as Imps, only faster and stronger.
* NoSneakAttacks: Imps have a tendency to helpfully screech and alert you to their presence ''before'' attacking.
* PaletteSwap: Nightmare Imps in ''Doom 64''. Just like the Spectres, Nightmare Imps have a partial InvisibilityCloak, and are colored differently (blue, in this case).
* RedEyesTakeWarning: In the classic series.
* SpikesOfVillainy: On their shoulders and knees.
[[/folder]]

[[folder:Demon (a.k.a. "Pinky") and Spectre]]
[[quoteright:200:https://static.tvtropes.org/pmwiki/pub/images/pinkytransparent.png]]
[[caption-width-right:200:"Pinky" in ''Doom I'' and ''Doom II'']]
[[caption-width-right:200:[[labelnote:Click here to see "Pinky" in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/pinky64transparent.png[[/labelnote]]]]
[[quoteright:200:https://static.tvtropes.org/pmwiki/pub/images/spectre_sprite.png]]
[[caption-width-right:200:Spectre in ''Doom I'' and ''Doom II'']]
[[caption-width-right:200:[[labelnote:Click here to see Nightmare Spectre in ''Doom'' for the [=PlayStation=]]]https://static.tvtropes.org/pmwiki/pub/images/psx_doom_nightmare_spectre.png[[/labelnote]]]]
[[caption-width-right:200:[[labelnote:Click here to see Spectre in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/spectre_30.png[[/labelnote]]]]
->''"Sorta like a shaved gorilla, except with horns, a big head, lots of teeth, and harder to kill. Don't get too close or they'll rip your fraggin' head off."''
-->-- Pinky's description in the ''Doom'' instruction manual

->''"Great. Just what you needed. An invisible (nearly) monster."''
-->-- Spectre's description in the ''Doom'' instruction manual

Hulking brutes that are tinted pink; while their official name is simply "Demon", almost everyone calls them Pinkies to avoid ambiguity. These guys get in your face as they have no ranged attack, but can do some serious damage. Spectres are versions of Demons that only appear as hazy outlines when encountered.
----
* AttackAttackAttack: Zigzagged. They seem to know only how to do is run at you and bite, but they'll often run back and forth erratically to make it hard to hit them.
* {{Cephalothorax}}: Their classic design is basically a giant demonic face with arms up near the temples running around on two legs. They do technically have a torso, it's just their oversized head and forward-hunched position makes head and torso indistinguishable when viewed from the front.
* CloseRangeCombatant: They have no ranged attacks, instead simply running up to try and bite you.
* DifficultyByAcceleration: Nightmare difficulty nearly doubles the speed of Pinkies and Spectres, making them much more of an immediate threat.
* EliteMooks: The Platform/PlayStation exclusive Nightmare Spectres are faster than regular Pinkies and have double health.
* FakeUltimateMook: Early-game Pinkies can be quite challenging for new players as they are fast and consume a lot of ammo, but as they gain arsenal and skills, these enemies become cakewalk.
* GiantMook: Huge, muscular beasts, that's not even mentioning their heads. Amped up in ''64'' where Pinkies are much more hulking in shape.
* GlassCannon: As explained above, their resistance is not so impressive and starting from ''Doom II'', they can be killed by one well-placed shot of your trusted Super Shotgun, but they are still powerful and nimble monsters who can spam bites, and if you happen to be back to them when they are part of an ambush, they can be rather dangerous.
* FoodChainOfEvil: Pinkies won't hesitate to attack and eat other demons in the classic series, especially Imps.
* ImmuneToFlinching: [[DownplayedTrope Well, not quite "immune"]], but Nightmare difficulty makes it so that their pain state is the shortest of any enemy in the game at 4 tics (or, 0.11 seconds). They will still flinch 70% of the time when being hit, but actually doing anything meaningful while they're flinching is borderline impossible; notably, the chainsaw goes from "reliable stunlock weapon against Pinkies" to "suicidal to use against Pinkies".
* InvisibilityCloak: The defining trait of the Spectre is its near-total transparency.
* InvisibleMonsters: Spectres are nearly invisible and almost transparent, making them hard to see.
* LeeroyJenkins: If they're part of a MonsterCloset or random ambush, they have a tendency to charge ahead of the main group (justified, due to only having a melee attack). On a positive note, this makes them very likely to get hit by other monster attacks from behind and are thus very susceptible to triggering a [[SetAMookToKillAMook Monster In-Fight]].
* LightningBruiser:
** Pinkies and Spectres are already faster than most of the enemies, but in Nightmare (and Ultra-Violence +), in addition to their strength and (small) resistance, they are [[SuperSpeed ridiculously fast]].
** To a lesser extent, the [=PlayStation=] exclusive Nightmare Spectres are faster (but not as fast as regular Pinkies on PC Nightmare mode) and tougher than them, and their VisibleInvisibility texture makes them harder to see in front of the dark visuals of the game.
* PaletteSwap: Spectre is this for the Pinky, being the same monster but with an InvisibilityCloak. The [=PlayStation=] port features a unique, much tougher version called Nightmare Spectre which has a transparent black color with cyan outlines around face and limbs - in other words, making it subtractively blended against the background. ''Doom 64'' recolors Spectres to yellow, though they're still mostly invisible.
* SpikesOfVillainy: They got two large horns on the sides of their heads.
* VisibleInvisibility: Spectres are partially transparent in their original incarnation.
* VolumetricMouth: The classic Pinky has a mouth that opens so wide it nearly touches the floor; it's much easier to notice when you see it from a side angle.
* ZergRush: Like the Lost Souls, Pinkies and Spectres do have a tendency to attack in groups. Though they also appear solo just as often, so they don't depend on this trope as much as Lost Souls do.
[[/folder]]

[[folder:Lost Soul]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/lostsoultransparent.png]]
[[caption-width-right:230:Lost Soul in ''Doom I'' and ''Doom II'']]
[[caption-width-right:230:[[labelnote:Click here to see Lost Soul in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/lostsoul64transparent.png[[/labelnote]]]]
->''"Dumb. Tough. Flies. On fire. 'Nuff said."''
-->-- Lost Souls' description in the ''Doom'' instruction manual

Disembodied horned skulls that are on fire. They can spawn from other enemies and simply fly into you as their only means of attack.
----
* AirborneMook: They are literally flying skulls who charge at you: coupled with their great mobility, this makes them fearsome enemies.
* CloseRangeCombatant: Lost Souls only charge ahead towards you, burning and biting you when they're close enough.
* FlamingSkulls: Disembodied ones, at that.
* FragileSpeedster: They go down after only a few direct hits, but be careful with your aim; the speedy buggers can be tough to hit. It is worth noting they have more health than all former humans and Imps in the first two games.
* GlassCannon: In ''VideoGame/Doom64'', they are much more vicious, attacking constantly as if the game is set to Nightmare!, but a single shotgun blast will kill them thanks to having their health reduced to half of their original incarnation. The Pain Elemental summons them two at a time, making said Elemental a priority target to prevent yourself from being killed quickly by a swarm of souls.
* GhostlyGlide: They move around through levitation, gliding through the air.
* LeeroyJenkins: Just like the Demons and Spectres, they charge ahead towards you due to only having a melee attack. And, like Demons and Spectres, Lost Souls also can create a [[SetAMookToKillAMook Monster In-Fight]] this way.
* MiniMook: They are the tiniest enemies of the game, one of the frailest, and starting from ''Doom II'', only intelligent weapons for Pain Elementals.
* NothingIsScarier: Lost Souls are the only monster in the classic ''Doom'' games that don't have a battle cry when they're alerted to your presence. This makes it kind of easy for them to sneak up on you if you're distracted or not paying attention. That being said though, they do make a loud hissing sound when they do their flying charge attack, and they share their roaming sound with the demon/spectre and cacodemon.
* YourHeadASplode: After being killed. The explosion is merely an effect, though, and won't affect anything near the Lost Soul.
* ZergRush: Lost Souls usually attack in groups and it's ''very'' rare to see a single one appear in a room/area all by itself.
[[/folder]]

[[folder:Cacodemon]]
[[quoteright:200:https://static.tvtropes.org/pmwiki/pub/images/cacodemontransparent.png]]
[[caption-width-right:200:Cacodemon in ''Doom I'' and ''Doom II'']]
[[caption-width-right:200:[[labelnote:Click here to see Cacodemon in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/cacodemon64transparent.png[[/labelnote]]]]
->''"They float in the air, belch ball-lightning, and boast one Hell of a big mouth. You're toast if you get too close to these monstrosities."''
-->-- Cacodemon's description in the ''Doom'' instruction manual

Floating blobs of red flesh with a single green eye, horns, and a nasty maw. They mostly attack by spitting energy blasts at you, but they will take a bite out of you if you get close enough.
----
* AirborneMook: They are one of the few enemies that are capable of flight: this gives them a greater mobility than other enemies who are stuck on the ground, and it makes your job a bit easier.
* AlienBlood: It bleeds red when shot, but its death sprites clearly have it bleeding blue. In some source ports like [=PRBoom=][=+=] and Crispy Doom, or mods like Smooth Doom, their blood is fixed to be blue when you shoot at them.
* BreathWeapon: They spit plasma at you.
* {{Cephalothorax}}: Basically a one-eyed, huge red floating head.
* CheshireCatGrin: Their SlasherSmile is amplified by the colossal size of their mouths.
* {{Cyclops}}: Has only one green eye for vision.
* DepartmentOfRedundancyDepartment: "[[https://en.wikipedia.org/wiki/Cacodemon κακοδαίμων]]" (kakodaimōn) is an Ancient Greek word meaning "evil demon", since "daimon" is a word for any kind of supernatural being, malevolent or otherwise. Since ''every'' demon in the world of ''Doom'' is evil, and there's nothing uniquely devious about these fellows, their name isn't terribly meaningful.
* EarlyBirdCameo: One appears prominently on [[https://doomwiki.org/wiki/File:Doomshare_title.png the original game's title screen]], but they don't show up in-game until Episode 2, making it a tantalizing sneak-peek for players of the Episode 1-only shareware version.
* EnergyBall: They spit these.
* EyeScream: Their death animation shows their eye flying out.
* FakeUltimateMook: The fact they're shown on the title screen of the first installement intents that they may be among the most dangerous demons in the game, but as you progress and your arsenal becomes bigger, you may consider them as simple nuisances before the end of Episode 2.
* GhostlyGlide: Since they have no legs, they float to get around the battlefield.
* MascotMook: They're one of the most recognizable of common enemies and so get a lot of marketing.
* PerpetualSmiler: They constantly display large, fanged grins.
* ShockAndAwe: Cacodemons attack by spitting a blast of ball-lightning.
* SlasherSmile: They display large smiles everytime and they are more than happy to spit balls at you.
* YouDontLookLikeYou: ''Doom 64'' changes their appearance drastically, making them dark-brown in color, giving them yellow eyes, and giving them arms with [[ChainedByFashion chains dangling from the wrists]], making them look more like the classic Pain Elemental.
[[/folder]]

[[folder:Baron of Hell & Hell Knight]]
[[quoteright:150:https://static.tvtropes.org/pmwiki/pub/images/baronofhelltransparent.png]]
[[caption-width-right:150:Baron of Hell in ''Doom I'' and ''Doom II'']]
[[caption-width-right:150:[[labelnote:Click here to see Baron of Hell in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/baronofhell64transparent.png[[/labelnote]]]]
[[quoteright:150:https://static.tvtropes.org/pmwiki/pub/images/hellknighttransparent.png]]
[[caption-width-right:150:Hell Knight in ''Doom II'']]
[[caption-width-right:150:[[labelnote:Click here to see Hell Knight in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/hellknight64transparent.png[[/labelnote]]]]
->''"Tough as a dump truck and nearly as big, these goliaths are the worst thing on two legs since Tyrannosaurus rex."''
-->-- Hell Knight's description in the ''Doom II'' instruction manual[[note]]this was a recycled description of the Baron from the first game's manual[[/note]]

->''"The Hell Knight was bad news, but this is Big Daddy. These bruisers are a lot like Hell Knights, but look a little different and are twice as tough to kill."''
-->-- The Baron of Hell's description in the ''Doom II'' instruction manual

Hell's elite. They are hoofed beings that walk upright and have a ram-like head, basically giant Satyrs. The Hell Knights are brown while the Barons are pink and tougher. They throw bolts of green fire and can slash with their hands. The Barons first appear at the end of the first episode of ''Doom'' as the final boss.
----
* AlienBlood: They ''also'' bleed red when shot, but their death sprites clearly have them bleeding green. Though the Barons bleed red in ''Doom 64''. In some source ports like [=PRBoom=][=+=] and Crispy Doom, or mods like Smooth Doom, their blood is fixed to be green when you shoot at them.
* AmazingTechnicolorPopulation: They come in shades of bright red and a dull brown, depending on their class.
* BigRedDevil: They're pink and brown, respectively, but they have a fairly classical goatman/minotaur-like look, with furry legs, cloven hooves and huge horns.
* TheBrute: They tower over most of their fellow demons, not to mention their formidable shape. While they're often portrayed as LargeAndInCharge for the lesser demons, they're dwarfed in both size and power by the higher ranking demons.
* DegradedBoss: From Episode 2 onward in the classic game.
* DualBoss: A pair of Barons (referred to in the Doom Bible as the "Bruiser Brothers") serve as the first "boss fight" at the end of Episode 1.
* EliteMooks: Both of them are bigger, tougher, and stronger Imps. The Barons of Hell take it further, as they have 1000 health, the third highest health of enemies in the first two games, under the Cyberdemon and Spider Mastermind.
* {{Fireballs}}: They attack by throwing green ones at the player.
* HellIsThatNoise: In the Platform/PlayStation ports and ''Doom 64'', Hell Knights let out [[https://youtu.be/dJc9Nxdx1Dg?si=Vh1XidML6n1GhLHq&t=82 a horrible agony scream]] when you kill them.
* LikeCannotCutLike: All monsters can hurt members of other species, but Barons cannot hurt Hell Knights nor vice-versa because of a special exception that explicitly codes out the ability for them to take damage from projectiles from their own species. You are able to sic Barons and Knights on other monsters, however, and if you can get them to use their melee attacks on one another or damage one another with a barrel, they'll still infight. Some ports also drop this exception.
* MightyGlacier: Knights and Barons don't move faster than regular enemies (they are as slow as regular Imps), but they have a good health bar for common enemies, and both their fireballs and physical attacks give you a run for your money.
* MovesetClone: Hell Knights have the same close and longe range attacks as Barons of Hell, only weaker.
* PaletteSwap: The Hell Knight is one. Oddly, they use a separate set of sprites, but is for all other intents and purposes treated as the same entity as the Baron of Hell, just with half the health (500 HP).
* ASinisterClue: In ''Doom 64'', they throw fireballs with their left arm.
* TheWorfEffect: The very first thing you see upon entering [=E2M8=] (the Cyberdemon's main boss level in the original game) is the mutilated corpses of four Barons, hanging against the walls. As the Baron is by far the strongest enemy you've encountered up to that point, and two of them were considered boss fight material in the first episode, this handily expresses just how strong the Cyberdemon is in a straight fight.
[[/folder]]

[[folder:Revenant]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/revenanttransparent.png]]
[[caption-width-right:230:Revenant in ''Doom II'']]
->''"Apparently when a demon dies, they pick him up, dust him off, wire him some combat gear, and send him back into battle. No rest for the wicked, eh? You wish your missiles did what his can do."''
-->-- The Revenant's description in the ''Doom II'' instruction manual

A walking skeleton with the ability to fire rockets off its shoulders.
----
* AIBreaker: Revenants are unique in that, if the player triggers their melee animation then moves out of range, their melee will simply miss; with other monsters who have both a melee and projectile attack, doing the same thing has them cheat and throw a fireball at the last second instead. [[DifficultButAwesome The timing isn't easy to pull off successfully]], but this quirk can be exploited by the player to punch Revenants out without having them shoot a projectile at them, or cancel out their retaliation projectile.
* ArbitraryWeaponRange: They won't fire their rockets if the player is too close, unless they get flinched and retaliate with a projectile. This results in a blind spot in their immediate vicinity, where the player is too close to use their missile and too far to punch.
* DemBones: They're walking skeletons.
* FragileSpeedster: They move quickly, but don't have too much health, and are easy to stunlock. That said, they have twice a Pinky's health.
* GlassCannon: They can be taken out with just two Super Shotgun blasts, but those missiles do quite a bit of damage if they hit and their homing qualities make them harder to avoid than other projectiles. Their melee attack [[{{Pun}} packs quite a punch]], too.
* GoodOldFisticuffs: Revenants use a punching attack when they get close enough to you.
* HomingProjectile: The rockets fired by Revenants have a chance of being homing missiles. These track you, but can't make sharp turns, allowing you to dodge them by using your superior maneuverability.
* JumpScare: Upon spotting the player, Revenants let out a very loud and sudden scream. This can be rather startling if you open a door that just happens to have one waiting for you on the other side--or if it's a door that opens on its own.
* LeanAndMean: They are very tall, as thin as you can expect from living skeletons, and among the vilest enemies in the game.
* MarionetteMotion: They move in an exaggerated, jerky way.
* ScarySkeleton: Towering skeletons armed with rocket launchers, who let out a terrifying screech before attacking.
* WackySoundEffect: The Revenants use a punching attack when you get too close and it sounds pretty cartoony.
[[/folder]]

[[folder:Mancubus]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/mancubus_1.png]]
[[caption-width-right:230:Mancubus in ''Doom II'']]
[[caption-width-right:230:[[labelnote:Click here to see Mancubus in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/mancubus64_sprite.png[[/labelnote]]]]
->''"The only good thing about fatso is that he's a nice wide target. Good thing, because it takes a lot of hits to puncture him. He pumps out fireballs like there was no tomorrow."''
-->-- Description of the Mancubus in the ''Doom II'' manual

Really fat demons with fireball cannons for arms. First introduced in ''Doom II: Hell on Earth'', they've become staples in every game since.
----
* ATeamFiring: They shoot fireballs in a spread-out pattern rather than straight at you, which complicates dodging.
* ArmCannon: Each arm has been replaced by a huge cannon, which they use to kill anything in their way.
* EvilSoundsDeep: They let out deep, gurgling and rather disgusting-sounding vocalizations. Their attack sound in particular is actually a sound of pigs squealing, but very low pitched; emphasizing both this and their obese stature.
* FatBastard: Larger that most demons and designed to look really fat, they’re also one of the nastiest enemies in the game.
* GiantMook: They're one of the biggest and largest demons in the game.
* IncrediblyDurableEnemies: They can suck up a ''lot'' of ammo before going down, having 600 HP.
* IronicName: Part of their name references the rather good looking [[SuccubiAndIncubi succubus or incubus]]... these guys are ''[[FatBastard anything but good looking]]''.
* {{Kevlard}}: They are fat, and they can take more damage than a Hell Knight.
* LeadTheTarget: A primitive version of this, anyway. A Mancubus's attack pattern is to shoot one fireball straight on and another to the right of the player, then one fireball straight on and another to the left, then two fireballs slightly to either side of the player. Because of this, people who are used to other demons and try to just mindlessly circle-strafe them can end up running right into their attacks.
* MightyGlacier: They are the slowest enemies in the game (as slow as the Zombieman), but their durability and damage output can be frightening.
* {{Multiboobage}}: It's not apparent in the game itself, but some pictures of the original maquette show the Mancubus to have three pairs of nipples; this is more visible in ''Doom 64''.
* PlayingWithFire: They wield implanted {{Arm Cannon}}s that shoot fireballs at enemies, and each attack fires three bursts of two fireballs.
* SmarterThanTheyLook: Their ATeamFiring gives the impression that they don't know how to aim properly, but they're actually one of the few demons to try to LeadTheTarget.
* TopHeavyGuy: Their legs are small compared to the rest of their body.
[[/folder]]

[[folder:Arachnotron]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/spiderdemon_sprite.png]]
[[caption-width-right:230:Arachnotron in ''Doom II'']]
[[caption-width-right:230:[[labelnote:Click here to see Arachnotron in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/arachnotron64_sprite.png[[/labelnote]]]]
->''"Maybe cybernetics wasn't such a great idea after all. Look what the demons have done with it. It seems unfair somehow you're not the only guy in Hell with a plasma gun."''
-->-- The Arachnotron's description in the ''Doom II'' instruction manual

A smaller version of the Spider Mastermind, they are strange beings mounted on four metallic legs with a plasma gun bolted to the front.
----
* AchillesHeel: While they fire a lot of projectiles, they remain stationary when doing so, making them very prone to cause monster infighting.
* BrainMonster / MyBrainIsBig: They are brains with faces in cybernetic weapons platforms.
* {{Cyborg}}: Quote ''Doom II'''s manual: "Maybe cybernetics wasn't such a great idea after all. Look what the demons have done with it."
* GiantMook: Their robotic bodies make them even bigger than they already are.
* GiantSpider: Not as big as Spider Mastermind, but still comparable to Mancubi.
* JumpScare: In the Platform/PlayStation ports and ''VideoGame/Doom64'', they let out [[https://youtu.be/dJc9Nxdx1Dg?si=uLywauH942p3ngxR&t=73 a hellish scream]] whenever they spot you and prepare for shooting.
* LightningBruiser: They are fairly nimble, deal a lot of damage, and they are as resistant as a Hell Knight.
* MoreDakka: Unlike other demons (outside of Nightmare difficulty), Arachnotrons will continuously shoot a sequence of projectiles without stopping as long as you remain in their line of sight.
* NoisyRobots: When they move, their legs make a heck of a lot of noise. Once they've seen you, they only stop [[ItsQuietTooQuiet when they're about to start shooting]].
* PlasmaCannon: Their weapon of choice doesn't give you any rest, but also allows you to spot where the plasma bullets come from.
* RedEyesTakeWarning: When shooting in ''Doom II'' and constantly in ''Doom 64''.
* SpiderTank: In ''Doom II'', their mechanical legs invoke this to some degrees in. ''Doom 64'' enforces the archnid design as they now look like scorpions.
[[/folder]]

[[folder:Pain Elemental]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/painelementaltransparent.png]]
[[caption-width-right:230:Pain Elemental in ''Doom II'']]
[[caption-width-right:230:[[labelnote:Click here to see Pain Elemental in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/painelemental64_sprite.png[[/labelnote]]]]
->''"What a name. And what a guy. Killing him is almost as bad as letting him live."''
-->-- The Pain Elemental's description in the ''Doom II'' instruction manual

Another floating blob of flesh with a single eye and unpleasant mouth. These guys are brown (unlike Cacodemons, which are red). They can create Lost Souls, which is how they attack.
----
* AirborneMook: One of the few enemies that are capable of flight.
* ArbitraryWeaponRange: If Doomguy gets right up close to a Pain Elemental, it'll be unable to spit out Lost Souls and will be easy pickings, though it'll still release them on death. Try this in ''Doom 64'', however, and it'll unleash a powerful explosion.
* AsteroidsMonster: They release three more Lost Souls upon death.
* {{Cephalothorax}}: Basically a one-eyed, huge brown floating head.
* {{Cyclops}}: Has only one red eye for vision.
* EliteMooks: Pain Elementals' mobility as floating heads and their ability to create Lost Souls make them elite versions of Cacodemons. They’re not more resistant than their red counterpart, though.
* HellIsThatNoise: Pain Elementals' sound effects stand out from the rest in how unique and strange they are. When spotting the player, they emit a garbled sped-up tiger growl, and whenever they are hit they let loose a digitized winding-down [="WAOoowww"=] noise.
* MookMaker: They produce up to 21 Lost Souls one after another, potentially less depending on how many Lost Souls currently exist in the level in total. The ''Doom 64'' version spawns them in pairs for double the pain.
* RedEyesTakeWarning: They're pretty horrifying to look at anyway, but the glowing red eye is an extra bit of warning.
* YouDontLookLikeYou: In ''Doom 64'', they're colored purple instead of brown, their eye is green instead of red, they have two mouths, they have a reptilian tail, and they have uncannily long black flowing hair which can be seen from behind.
[[/folder]]

[[folder:Arch-Vile]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/archietransparent.png]]
[[caption-width-right:230:Arch-Vile in ''Doom II'']]

->''"One of the worst of a bad lot. You can't think of enough rotten things to say about him. He's fast, hard to kill, casts spells, and resurrects dead monsters! At least these suckers are rare."''
-->-- The Arch-Vile's [[DemonicSpiders apt]] description in the ''Doom II'' manual

A particularly powerful being that can revive fallen monsters. Also attacks the player with flames that can erupt underneath the target.
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* AchillesHeel: They're really fast, but in terms of attack speed, their only attack is to cause a flame explosion which does deal a lot of damage, but it takes quite the time for it to actually happen, giving the Doomguy the time to find cover. They make up for this by having a 3% pain chance.
* AlwaysAccurateAttack: Its flame attack will ''always'' hit you unless you can put something between it and you to block it from seeing you. Trees or other monsters won't work, for the record - you have to find a wall.
* AntiFrustrationFeatures: They lack the ability to resurrect other archviles, as otherwise multiple archviles would be nearly unbeatable. They are also unable to resurrect Cyberdemons and Spider Masterminds.
* BossInMookClothing: Has a lot of health (second only to the monsters used as bosses), can resurrect fallen enemies, and has a powerful attack that can only be dodged by getting out of his line of sight.
* CombatMedic: Their flame attack deals a lot of damage and they have the exclusive ability to resurrect other enemies that were killed.
* EarlyBirdCameo: Appears immortalized by the "alien" wall texture in the first ''Doom'', alongside the Baron of Hell and the Icon of Sin.
* EliteMooks: While Nightmare Imps, Hell Knights and Barons of Hell are straightforward stronger versions of [[TheGoomba Imps]], Arch-Viles are more sophisticated: not only [[LightningBruiser they are mobile and tough]], but their flames can reach you by the only condition that they can see you, and they can resurrect {{Mook}}s.
* EvilLaugh: [[HellIsThatNoise The way they let you know]] [[OhCrap how much you are screwed]]. They let loose a warbling, rising one when spotting you, and emit a... ''strange'' moan when roaming.
* ImmuneToFlinching: Not quite immunity, but the Arch-Vile still stands out for having the lowest pain chance of all demons: a little over 3% per hit taken. 20 pellets from a point-blank Super Shotgun blast has only an average 50% chance of inflicting a pain state on them, making that a risky gamble. For comparison, the next-toughest demon (the Cyberdemon) has an approximately 8% pain chance.
* InterfaceScrew: Their attack causes a flickering flame to cover your vision. When that happens, you have to get behind cover to break line of sight and stop the spell from fully charging up and damaging you, but it can be tricky to find a path when all you can see is fire, especially if there are lots of other monsters in the room.
* LeanAndMean: Their body type could be compared to a severely emaciated human, and they're not called Arch-''Vile'' for nothing.
* LightningBruiser: They can move really fast (in fact, they're the second fastest enemy other than a charging Lost Soul), hit hard with their flame attack, and can take quite a bit of punishment before going down (700 HP, more than a Hell Knight or a Mancubus, only being below [[DegradedBoss Barons of Hell]]).
* MookMedic: In ''Doom II'', they resurrect fallen enemies.
* MoralMyopia: Screams "why?!" upon death because he is Hell's "[[ShootTheMedicFirst evil healer]]". He doesn't understand why anyone would want to kill him since he's only doing good by resurrecting his fellow demons. [[HypocriticalHumor And then burning you to death.]]
* OnlySaneMan: Their tactic of resurrecting other monsters is the only example of any demon actually ''helping'' its cohorts, rather than mostly getting in each other's way and starting fights. [[NotSoAboveItAll That still doesn't stop them from getting into fights with other monsters themselves, either.]]
* OverlyLongFightingAnimation: The Archvile's flame attack has a long animation before it connects, giving Doomguy ample time to find cover.
* PlayingWithFire: Creates a flame underneath you as an attack. However, the fire doesn't hurt you at first, but after a charge-up time it'll explode and deal a lot of damage.
* SetAMookToKillAMook: Uniquely, no monsters will ever target an Arch-Vile intentionally; they may hit one while attempting to shoot something else, but they will take any number of retaliatory flame blasts after doing so and never purposely aim for the Arch-Vile.
* SupportPartyMember: A lone Arch-Vile is not much of a threat: its only attack, while extremely damaging, requires uninterrupted line of sight for several seconds before it goes off, so it can be blocked simply by hiding behind an obstacle. However, in the heat of combat, you may find yourself in a position where it's not possible to get to cover in time, at least not without putting yourself in other enemies' line of fire. And if you ignore it, it will revive the other demons you kill, meaning you'll probably want to ShootTheMedicFirst.
* WeaksauceWeakness: They only have one attack, which has by far the longest "wind up" time of any in the game, during which they are completely vulnerable to attack (or running out of line of sight if you're low on ammo). Likely because of this, they have the lowest flinch chance of any monster (less than the cyberdemon even) to make it harder to interrupt their attack. If you hit them with the super-shotgun at close range you can still interrupt them about 25 percent of the time as each "pellet" counts as a separate hit.
[[/folder]]

[[folder:Wolfenstein SS]]
[[quoteright:100:https://static.tvtropes.org/pmwiki/pub/images/wolfensteintransparent.png]]
[[caption-width-right:100:Wolfenstein SS in ''Doom II'']]
->''"Mein leben!"'' [[labelnote:Translation]]My life![[/labelnote]]
-->-- The SS' death quote

A [[ThoseWackyNazis Nazi soldier]] taken from ''VideoGame/Wolfenstein3D'', appearing only in two secret levels in ''Doom II''. Several versions of ''Doom II'' replace them with ordinary monsters so the game could be sold in Germany.
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* AdaptationalWimp: The SS in ''Wolfenstein 3-D'' were pretty nasty, being EliteMooks that dealt a lot of hitscan damage and took just enough in return to be unpleasant to bring down in groups. In ''Doom'', their fire rates, accuracy, and health take a dive, and they are now almost completely ineffectual, in addition to being significantly shorter than Doom's other humanoid enemies (in contrast, they were as tall as or even taller than Blazkowicz in Wolf 3D). They also replace the common brownshirt Nazi guards that served as {{mooks}} in the original Wolf 3D, meaning that you now encounter them in numbers that would have been like walking in front of a firing squad in the original--making it all the more obvious when a single super shotgun blast turns a whole group of them into red jam. For a bonus, the second secret level you encounter them in is almost ''designed'' to result in them infighting with a Cyberdemon, which will usually end in the Cyberdemon killing them all with its rockets.
* TheArtifact: Enemies in ''Wolfenstein 3-D'' only have one sprite for attacking, due to the game not having to accomodate infighting or co-op players being attacked. This means when they're shooting someone who's not you, it'll look like you're being shot regardless.
* EasterEgg: Not a canon enemy, appearing only in two secret levels.
* {{Ghostapo}}: They fight alongside demons against Doomguy, implying they're assisting (or at least not stopping) the demonic invasion.
* GratuitousNazis: The presence of ordinary human Nazis in a game about slaying demons in a futuristic setting is pretty jarring to say the least. The intro to [=MAP31=] [[HandWave Hand Waves]] it by describing it as part of Hell, but this creates a VoodooShark because the level where you find the entrance to the secret map ([=MAP15=], Industrial Zone) takes place before Doomguy enters the portal to Hell.
* HelpfulMook: [[DownplayedExample Downplayed.]] Like the green-haired zombie enemies, these guys drop pistol clips (bullet ammo) when killed. Also, they seem to be prone to infighting with each other due both to their inaccuracy and the way that hitscan enemies work in Doom in general, something that was not present in their Wolfenstein incarnation.
* {{Hitscan}}: They shoot in two-round bursts, unlike the other hitscan enemies (a side-effect of having two frames in their firing animation, unlike the Former Humans they were coded from.)
* ImperialStormtrooperMarksmanshipAcademy: Their accuracy and damage have been significantly lowered from their ''Wolfenstein'' origins.
* NoSwastikas: As mentioned before, are removed from some releases of ''Doom II''.
* PhenotypeStereotype: Blond-haired and blue-eyed to the last one.
* VocalDissonance: Despite having their own unique "enemy spotted" and death sounds, the sound they make when damaged is identical to the sound made by normal zombie enemies.
[[/folder]]

!!Bosses
[[folder:Cyberdemon]]
[[quoteright:230:https://static.tvtropes.org/pmwiki/pub/images/cyberdemontransparent.png]]
[[caption-width-right:230:Cyberdemon in ''Doom I'' and ''Doom II'']]
[[caption-width-right:230:[[labelnote:Click here to see Cyberdemon in ''Doom 64'']]https://static.tvtropes.org/pmwiki/pub/images/cyberdemon64_sprite.png[[/labelnote]]]]
->''"A missile-launching skyscraper with goat legs. 'Nuff said."''
-->-- The Cyberdemon's description in the ''Doom II'' instruction manual

Hell's most fearsome creature and the boss of episode 2 of ''Doom''. He is a towering creature with a metal leg and a rocket launcher for an arm.
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* ArmCannon: A rocket launcher, to make things worse.
* ArtificialLimbs: Metal legs and a cannon arm.
* AttackAttackAttack: He is specifically programmed to attack more often than most monsters, and always fires volleys of three rockets each time he attacks, whereas most monsters just throw one projectile per attack.
* BossInMookClothing: Even after he becomes [[DegradedBoss more common]], the Cyberdemon still remains the strongest enemy and one of the toughest.
* BreakoutVillain: First he was TheDragon to the Spider Mastermind. In subsequent games, he keeps this position with the Icon of Sin, being the last obstacle before him (''Doom II, Plutonia'') or just the FinalBoss (''Doom 3, No Rest for the Living''). Nowadays he's one of the most recognizable elements of the franchise, being put on the front cover of ''Doom II'', becoming the first boss of ''DOOM 2016'', and returning as a Super-Heavy enemy called a Tyrant in ''DOOM Eternal''.
* ClimaxBoss: He's the culmination of the entire episode, and initially seemed to be the BigBad, until you faced off against the Spider Mastermind.
* ContractualBossImmunity: Like the Spider Mastermind, he is immune to splash damage. This effectively gives him nearly 70 percent resistance to the player's rockets.
* {{Cyborg}}: "Half unfeeling machine, half raging horned devil", as said by the SNES manual.
* DamageSpongeBoss: He can take an incredible amount of punishment in all the games it's in, as he has ''4000'' HP. As the [=GamePro=] parody protip says:
--> PROTIP: To defeat the Cyberdemon, shoot at it until it dies.
* TheDragon: In the first game, he's the second in command; it's the Spider Mastermind who's the true leader of the invasion and the final boss. In the second, he is the final obstacle in the last regular level, "The Living End", just before the player faces the Icon of Sin. In ''Doom 64'' 2020 campaign ''The Lost Levels'', he fights alongside the last remains of the demons' army before you face the Mother Demon.
* EstablishingCharacterMoment: The first thing you see when you enter the Tower Of Babel (the level where he first appears) is the dismembered corpses of four Barons of Hell, the DualBoss of the first episode, strung up on the walls, which instantly leads you to wonder [[TheWorfEffect "What kind of monster could do this to Barons of Hell?"]] [[note]]And then you wonder [[FridgeLogic how he strung them up with only one hand]].[[/note]]
* FlunkyBoss: It depends on the level, the difficulty setting, and if playing in co-op, but sometimes the Cyberdemon is accompanied by other monsters when you fight it. For example, the first Cyberdemon you encounter in the "Tower of Babel" level in Episode 2 of the original ''Doom'' is accompanied by Lost Souls.
* HellIsThatNoise: Has a very loud and unmistakable stomping noise when he walks.
* ImAHumanitarian: As noted above, his lair contains four mutilated corpses of Barons of Hell, which he seems to have eaten.
* LateArrivalSpoiler: He is not mentioned in the first game's instruction manual, so as to keep his climactic appearance in Episode 2 a surprise, but players will already know to expect him at some point just by looking at the cover of ''Doom II'', which he appears on.
* LightningBruiser: He's the fastest-moving monster in the game apart from the Archvile, his rockets are faster than the fireballs of the other demons and substantially more powerful (able to instakill or at least do serious damage to the relatively GlassCannon player), he has 4000 HP (the highest in the first two games) ''and'' he has an immunity to splash damage unlike his Baron brethren.
* LudicrousGibs: His death animation has his cybernetic components explode, turning him into a splatter of blood and gore. In the end, only his hooves remain.
* TheManInFrontOfTheMan: Possibly. While the Spider Mastermind is the FinalBoss of the original ''Doom'', at the end of ''VideoGame/DoomII'' there is a sort of monster "roll call" showing the monsters in order of weakest to strongest. The Cyberdemon comes last, ''after'' the Spider Mastermind, which implies he is really the most powerful (other than the Icon Of Sin of course), but is ranked lower in demons' hierarchy because of the Spider Demon's supposedly superior intelligence.
* MascotMook: Not anywhere near as popular as the Cacodemon, but still the second most recognizable enemy in the game and appears on the cover art and title screen of ''Doom II''.
* OneHitKill: His rockets really ''hurt'', and a direct hit will do enough damage to be guaranteed fatal to a player with the default 100% health and no armor. And with his rockets dealing a possible maximum of around 280 damage, it'll take the player getting their health boosted beyond 100% and good armor to make surviving a direct rocket a sure thing. [[ThereIsNoKillLikeOverkill Of course, the Cyberdemon never fires just one rocket at a time.]]
* RecurringBoss: He keeps making appearances after episode 2, but unlike the DegradedBoss that are Barons of Hell, he appears a lot more sparsely; the most frequently he appears are in ''Plutonia''[='s=] secret maps (4 times in Cyberden, 13 times in Go 2 It).
* UnexplainedRecovery: The ending text of "The Shores of Hell" seems to imply that the Cyberdemon is a singular individual, which leads one to question how he comes back in later levels after exploding into a giant shower of blood. Of course, this can be easily accepted if it's just a species of demon like all of the others, which is also implied in the small number of levels which features multiple Cyberdemons at once, like level 17 of ''Doom 64''.
* WakeUpCallBoss: Twice as much health as the "Bruiser Brothers" combined and able to splay you across the floor in two-three direct hits or even one shot you if you don't have both boosted health and armor. Hope you figured out how to circlestrafe by now.
[[/folder]]

[[folder:Spider Mastermind]]
[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/spidermastermindtransparent.png]]
[[caption-width-right:350:Spider Mastermind in ''Doom I'' and ''Doom II'']]
->''"You guess the Arachnotrons had to come from somewhere. Hi, Mom. She doesn't have a plasma gun, so thank heaven for small favors. Instead, she has a super-chaingun. Crap."''
-->-- The Spider Mastermind's description in the ''Doom II'' manual

The final boss of episode 3 of ''Doom'', and the sinister mastermind behind the demonic invasions of Phobos and Deimos. A gigantic version of the Arachnotrons, she too is a creature mounted upon four titanic metal legs and a chaingun for defense.
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* AchillesHeel: The BFG's tracer spread is best used against wide targets, dealing up to about 3500 damage to a single target. The Spider Mastermind is the widest enemy in the game, and at 3000 HP, it's very probable to OneHitKill her using it -- if not leave her easily finished off by another shot or a different weapon.
* BigBad: In the plot of the original game. [[AlwaysABiggerFish 2 and 64 introduced higher ranking demons since]], but the moon base invasions were all the Spider's idea.
* BossArenaIdiocy: In ''Doom II'', she is often in situations where she can be killed quite easily thanks to the environment or because of nearby enemies turning against her. See ButtMonkey and VillainDecay below for specifics.
* BossInMookClothing: Even if the developers love to humiliate her, she still can be considered this after her degradation because of her resistance and her favored weapon.
* ButtMonkey: Most of her appearances in ''Doom II'' are deliberately designed so that the player can easily get her killed without actually having to do much. Typically, this is done by placing her in a crowded space with other powerful monsters (such as the Cyberdemon, a group of her own Arachnotron "children", or even [[MirrorMatch herself]]) that are very likely to start a fight with her and win, but most humiliating of all is Map 6, "The Crusher", where (on Ultra-Violence difficulty and higher) she can be squashed flat by the titular crusher with a simple flip of a switch.
* ContractualBossImmunity: She is immune to splash damage. This effectively gives her nearly 70 percent resistance to rockets.
* {{Cyborg}}: A tremendous brain attached to a set of mechanical legs.
* EvilGenius: She has a massive brain and is the mastermind behind the original demonic invasion. Likely the only reason she is above the Cyberdemon is that she is smarter.
* GatlingGood: Spidey's original incarnation has her blasting off with a super chaingun.
* GiantSpaceFleaFromNowhere: Unlike the Cyberdemon, her existence isn't foreshadowed at all before her appearance in the final boss battle, nor is her status as the commander of the invasion established until you've already defeated her, and it's doubtful anyone would have ever expected the leader of Hell to be a cyborg brain-spider thing instead of, y'know, {{Satan}}.
* GiantSpider: [[SpiderTank A mechanical one, in fact.]]
* GoodNewsBadNews: As noted in the ''Doom II'' manual, the Spider Mastermind has a souped-up chaingun as her main weapon:
--> ''She doesn't have a plasma gun, so thank heaven for small favors. [[ThisIsGonnaSuck Instead, she has a super-chaingun.]] [[OhCrap Crap.]]''
* HellIsThatNoise: Makes very loud pounding noises when she walks, which can be heard from whole rooms away.
* KingMook: Even if she appeared before them, she's still a larger version of the Arachnotrons, with a more devastating weapon.
* MonsterIsAMommy: Not actually true, but the manual refers to the Mastermind as the mother of the Arachnotrons.
--> ''You guess the Arachnotrons had to come from somewhere. Hi, Mom.''
* MoreDakka: She uses a chaingun and never misses the opportunity to shoot you when you're in her sight.
* MyBrainIsBig: She's an immense creature, and most of her organic component seems to consist of brain tissue. Not for nothing is she called the [[MeaningfulName MasterMIND]].
* MythologyGag: Her death animation is very similar to how Hitler dies in ''VideoGame/Wolfenstein3D'': She basically collapses into a pile of gore with only her facial features still recognizable.
* NoisyRobots: Her legs produce a loud pneumatic sound as they move - she sounds almost like a steam engine when she gets going.
* RecurringBoss: Though not as often as the Cyberdemon, the Spider Mastermind reappears past the original game's third episode. She reprises the role of FinalBoss in the additional fourth episode, and appears in various ''Doom II'' levels (including one where ''two'' Masterminds appear, as well as another where she teams up with the Cyberdemon).
* RedEyesTakeWarning: Hardly needed, but her glaring crimson eyes emphasize her monstrous nature.
* UnexplainedRecovery: As with the Cyberdemon, the ending text after your first encounter with the Spider Mastermind seems to claim that there is only one of her, yet she returns in "Thy Flesh Consumed" and ''Doom II'' ''after'' being killed at the end of "Inferno". Also as with the Cyberdemon, she occasionally appears in pairs (such as in Map 28 of ''Doom II'', "The Spirit World", on Ultra-Violence difficulty and higher), so this could be explained as her simply being a species of demon after all.
* VillainDecay: While it's expected that the boss enemies become less unique after their initial appearance, the Spider Mastermind stands out for practically being degraded to ButtMonkey status in ''Doom II'' (compared to her sole appearance in Episode 4 of ''The Ultimate Doom'', which intentionally works to make her more dangerous as a proper final boss). Every encounter with her has a gimmick that makes her almost effortless to defeat:
** Her first appearance, if the difficulty is high enough, is in Map 6, The Crusher. As the map name suggests, all you have to do is flip a switch to have a DescendingCeiling she can't get out from under slowly smash her to bits.
** In Map 20, Gotcha!, the Spiderdemon appears on a platform facing a Cyberdemon. This makes it very easy to [[SetAMookToKillAMook lure the two of them into infighting]], then finish off whoever's left while they're greatly weakened.
** Map 23, Barrels o' Fun, is the least gimmicky Spider Mastermind fight in ''Doom II'', but she's surrounded by Arachnotrons who will gladly tear their own mother apart if coaxed into infighting.
** Map 28, The Spirit World, has not one, but ''two'' Spider Masterminds. Right by them are several Invulnerability Spheres, giving you more than enough invincible time to not have to worry about them. You can also make the two Masterminds fight each other, as enemies with {{Hitscan}} attacks can harm others of the same type.
[[/folder]]

[[folder:Icon of Sin]]
[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/icon_of_sin_6.png]]
[[caption-width-right:350:''"Oremor nhoj, em llik tsum uoy, emag eht niw ot."'']]
->''"The horrendous visage of the biggest demon you've ever seen crumbles before you, after you pump your rockets into his exposed brain. The monster shrivels up and dies, its thrashing limbs devastating untold miles of Hell's surface."''
-->-- Excerpt from the ''Doom II'' ending screen

The leader of Hell and the final boss of ''Doom II''. Spawns demons to defend itself.
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* AttackItsWeakPoint: To kill it, you have to fire rockets into the hole in its forehead.
* AttackOfTheFiftyFootWhatever: All the player ever sees is its head, but the ending implies that it's massive enough to destroy most of Hell in its death throes. [[spoiler:''Eternal'' shows that it can cause serious destruction on Earth as well.]]
* BigBad: It's the absolute ruler of Hell (at least if you discount the Mother Demon) and it leads Earth's invasion in the second game.
* BodyHorror: The way to kill him is to fire rockets in his open forehead. [[spoiler:If you manage to go inside, you'll see Creator/JohnRomero's head impaled on a spike.]]
* ChekhovsGunman: Its face shows up on stage architecture in both games before the player even knows about its existence.
* ContractualBossImmunity: In a reversal from the other bosses, rockets are the ''only'' weapon that can damage it - it's the BFG that it's specifically designed to be immune to.
* DeathByCameo: Mechanically speaking, the "demon" is actually a big wall with a hole. The actual entity that takes damage is [[spoiler:the head of John Romero impaled on a spike]].
* DegradedBoss: It reappears at the end of Map 15 in ''Master Levels'', but it's smaller due to the wall's size and much easier (as you're now positioned from a more convenient spot to hit its weak point directly). Also, it's no longer the FinalBoss, as that level isn't the last in the collection.
* DigitizedSprites: [[spoiler:The sprite for the severed head deep inside the hole was ripped from [[https://doomwiki.org/w/images/0/0a/Wilbur-Carmack-Romero-1994.jpg a photograph of John Romero]] taken for ''Wired'' Magazine.]]
* GameplayAndStorySegregation: The ending text for ''Doom II'' states it to have massive limbs that it destroys Hell with in its death throes, but ingame it's just an inanimate texture on a wall.
* GenericDoomsdayVillain: As he has absolutely no personality or backstory other than "giant demon who creates other demons", he's about as generic as a doomsday villain can get.
* MookMaker: Its only real attack in the game is spawning an endless supply of other enemies.
* NoNameGiven: The boss was never given an official name in-game; "Icon of Sin" is the name of the level you encountered it. But since there was nothing else in the level, the fandom used the level's name as the boss's name out of convenience. It took 22 years for [[WordOfGod John Romero]] to [[https://i.gyazo.com/da648911e46e39f46e74bc7c0a5ad6d5.png confirm]] Icon of Sin was also the name of the demon. The manual of ''Final Doom'' gives its ''Doom II'' incarnation name as "Baphomet", though that still leaves the question of the names of its incarnations in the two ''Final Doom'' [=WADs=].
* OneHitKill: While his cubes don't aim at you, if they do hit you get {{telefrag}}ged. This kills you instantly even in God Mode, since it only protects against up to 1,000 damage while a telefrag is coded to deal 10,000.
* PublicDomainCharacter: It's modeled after [[https://en.wikipedia.org/wiki/Baphomet Baphomet]], a figure in occult symbology that's widely revered by Satanists, making it one of the few demons in the series to have genuine religious roots. Baphomet as a religious figure is not actually connected to Hell or demons, however, so some ArtisticLicense still applies.
* PuzzleBoss: To get at its weak point, you have to ride a rising pillar. Because the vanilla ''Doom'' engine has a vertically fixed camera, you have to time your attacks to ''just'' before the pillar reaches the top, with the additional wrinkle that there's a delay between pulling the trigger and the rocket launcher actually firing.
* RecurringBoss: A series-wide example, as the Icon of Sin reprises its role as FinalBoss for both campaigns of ''VideoGame/FinalDoom''. It also reappears in one of the Master Levels (albeit as a DegradedBoss since its level isn't the last).
* RushBoss: Likely to keep it from being too challenging for players to kill, the Icon's base entity (John Romero's head) only has 200 HP, in stark contrast to other bosses' HP (especially the Cyberdemon's 4000 HP). However, it can still be tough to defeat the Icon, since all demons save for bosses (Cyberdemon and Spider Mastermind) can be spawned through the cubes the Icon summons, and if left unchecked will become quite numerous. This even includes Arch-Viles, though the odds of one being spawned is fortunately less than 1%.
* SatanicArchetype: As far as you can tell, he is the ruler of hell and the demons. He's probably not the literal Satan from Literature/TheBible though, considering there's more than one of his kind.
* SdrawkcabSpeech: The sound that plays when he first sees you is backmasked.
-->"Oremor nhoj, em llik tsum uoy, emag eht niw ot."
* StationaryBoss: By virtue of being a wall texture with a hole in it, the Icon of Sin can't move.
[[/folder]]

[[folder:Mother Demon]]
[[quoteright:222:https://static.tvtropes.org/pmwiki/pub/images/motherdemontransparent.png]]
[[caption-width-right:222:Mother Demon in ''Doom 64'']]
->''"An unseen entity from beyond, cloaked by radiation, has rejuvenated the rotting carnage of Phobos. The demons are back. Your assignment is clear. Total annihilation."''
-->-- Description on the product page of ''Doom 64''

The final boss of ''Doom 64''. A demon with the ability to resurrect other demons much like the Arch-Vile, and making them stronger than before as she does. She single-handedly rebuilds the demon army, forcing the Marine to put them down once again.
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* BigBad: The ultimate boss of ''Doom 64'', and technically superior even to the Icon of Sin, going by the lore.
* BigCreepyCrawlies: She takes the form of a giant wingless moth.
* DamageSpongeBoss: She's the most resistant enemy in classic games with a total of '''''5300 HP'''''.
* GameplayAndStorySegregation: The game's backstory makes her out to be an Arch-Vile on steroids, only needing to pass by a demon to resurrect it [[CameBackStrong stronger than before]], explaining how Hell's forces came back after ''Doom II''. However ingame she does not have any such reviving ability, and so [[AntiFrustrationFeatures all the demons you have to kill in her arena before fighting her will stay dead]].
* PlayingWithFire: Her attack involves firing out four fire trails across the ground in the four cardinal directions from her, that will send the player soaring into the sky on contact much like the Archvile's attack, which is then immediately followed by her launching four fireballs that home in the player like the Revenants' rockets.
* ThereIsAnother: [[spoiler:The lost levels of ''64'' reveal there are two of them, and they're sisters.]]
[[/folder]]
----