* The infamous [[HarderThanHard Nightmare!]] difficulty wasn't in the original release of the game. People who beat it actually started complaining to Id that Ultra-Violence was ItsEasySoItSucks for the hardest difficulty, so the devs [[GoneHorriblyRight took them up on their challenge]] on patches and future re-releases with a difficulty that [[LampshadeHanging isn't even remotely fair.]]
* The DOOM Wiki's page on the Doomguy has this little Gem:
--> "The introduction of "jump" and "duck" controls in source ports such as ZDoom and Skulltag , although not canon, seem to quash the widespread [[WildMassGuessing rumours]] of the 1990s that the Doom marine was a paraplegic transporting himself by a [[CrazyAwesome rocket powered wheelchair.]]"

!!Doom 2
* From the ending of ''Doom II'':
-->The invasion is over. Earth is saved. Hell is a wreck. [[FridgeLogic You wonder]] [[LampshadeHanging where bad folks will go when they die, now.]]
* [=MAP20=] of ''Doom II'', ''Gotcha!'', becomes this in retrospect- the demons deployed their two most powerful monsters in the same spot, thinking it a foolproof plan. If Doomguy plays his cards right, they'll end up... [[EpicFail fighting each other]].
* The Xbox 360 Arcade port of ''Doom II'' has achievements that quote the Doom comic, including "You Have Huge Guts" for killing a Cyberdemon with your fists.

!!Doom 3
* In Doom 3, after you get your PDA from the receptionist, stick around and read the report he's typing on his computer. He'll eventually add a supplemental section complaining about your rudeness and how you were reading everything he typed.
* Near the end of Doom 3, long after the forces of Hell have entrenched themselves on Mars, you find a terminal with a document for you to download. The document in question? [[BreadEggsMilkSquick A helpful guide one of the demons wrote on how to preform a ritual sacrifice]].

!!Doom (2016)
* During the E3 presentation of the 4th game, Doomguy comes across a palm-reader he doesn't have clearance for. He tracks down the corpse of someone who did have clearance, casually tears off his (remaining) arm and uses that to clear the way.
* Doomguy [[https://www.youtube.com/watch?v=SZGjA0O-PsI fist bumps a Space Marine bobblehead.]]
** The Space Marine bobbleheads in general, since [[SoundtrackDissonance they play a cheerful chiptune version of "At Doom's Gate"]] when collected, and the SuperDeformed forms of the bobbleheads [[{{Bathos}} look pretty damn ridiculous]] considering the more realistic looks of Doom 2016.
** Especially in the credits where you see the Space Marine bobblehead face against a Pinky.
* Doom Marine's antics in general.
** In the Argent Tower, Doomguy has to remove the filters that turn Hell energy into the safe(r) Argent energy. Hayden tells him to carefully remove the filter, and for a second, Doomguy seems to be about to do so. Then he just stomps the damn thing to break it. Hayden bitches each time he does this to a filter.
** Punching the weapon mod drones. [[UngratefulBastard Really Doomguy]]?
*** Apparently, it's because Doomguy would usually have to pay credits to get the equipment. Doomguy has no credits, ergo punch to dislodge.
** During the prologue, Doomguy gets two calls from [[MissionControl Dr. Samuel Hayden]], [[CardCarryingVillain who all but outright states he's responsible for the demons being on Mars]] [[WellIntentionedExtremist while trying to claim it's for "the greater good"]]. [[ShutUpHannibal Doomguy shuts up Hayden both times]] [[TalkToTheFist by smashing the screens Hayden is calling him on]].
* Dying horribly by burning and melting to death in molten steel? Bad. [[Film/Terminator2 Doomguy giving the thumbs-up as he's finished off by the horrific burning death? Hilarious.]]

!!The [[Comicbook/{{Doom}} tie-in comic]]
* The comicbook in its entirety. Special mentions go to:
** "[[RuleOfThree Stupid! Stupid! Stupid]] Imp! You're stupid! And you're gonna be stupid and '''dead!'''"
** "Imps? Zombies? You think you can get me?!? (''Thinks to himself'') Wait. Maybe they don't think. (''Starts yelling'') Well I do! And I think you're dead! Dead! '''Dead!''' '''DEAD!'''"
** "Rip and tear! Rip and tear your guts! You are huge! That means you have '''HUGE GUTS! RIP AND TEAR!''' Oooh, here comes the night train! Choo choo '''CHA-BOOGIE!'''"
** "[[IncomingHam Knock knock who's there? ME!]] [[MadnessMantra ME ME ME ME ME ME ME ME]]"
** "Aah! [[ChainsawGood Chainsaw! The Great Communicator!]]"
** "Now I'm RADIOACTIVE! [[CaptainObvious That can't be good!]]"
* Meta. [[http://www.doomworld.com/10years/doomcomic/ This]] summary about the comic written by Doomworld.

!!Game Reviews
* The [[https://web.archive.org/web/20120104155012/http://www.next-gen.biz/reviews/doom-review EDGE review]], starting with the infamous line "[[ComicallyMissingThePoint If only you could talk to the monsters...]]"
* [=GamePro's=] infamous "[[http://knowyourmeme.com/memes/protip PRO TIP]]: Shoot the Cyberdemon until it dies." [[spoiler:It's fake--the "magazine scan" is Photoshopped together--but it's funny all the same.]]

!!Game Mods
* The Rickroller. We would say "nuff said," but no; [[http://www.youtube.com/watch?v=SL0VncaV0D0 you've gotta see this one]].
* One visual glitch is that, regardless of where on the image an enemy's weapon is, its attack emerges from its midriff. This resulted in unintended humour in the "Ultimate [[Franchise/TheSimpsons Simpsons]]" Doom mod, where the Cyberdemon is Mr. Burns... and [[PhallicWeapon his rockets emerge from his crotch]].
* TheCraftyTitan's Doom Hack... better known as [[VideoGame/{{Touhou}} Yukkuri]] Doom, in which everything runs on RuleOfFunny and the Yukkuris are in no short supply. Oh and the rocket launcher is replaced with [[VideoGame/MetalSlug RAWKET LAWNCHAIR]] literally. https://www.youtube.com/watch?v=dske-7XjaiA part of the game in action.
* Russian Overkill gives the player intentionally [[GameBreaker game breakingly-powerful]] weapons, items which can casually give the player hundreds or thousands of HP in health and 100% damage reduction armor, and [[YouNukeEm allows you to launch several flavors of nuclear weapon]] into your foes. What do they get? Health multipliers if you're feeling generous. Even the notorious nuts.wad becomes a joke with the [[NoKillLikeOverkill absurdly overpowered arsenal]] you have available to you. Some highlights of your very extensive arsenal include:
** A character who can launch [[Machinima/TheGmodIdiotBox explosive, homing CRT monitors]]. Or drop [[{{VideoGame/Worms}} a certain highly-explosive donkey statue]].
** A character who can [[Film/ThreeHundred Sparta kick]] hard enough to one-shot a Cyberdemon.
** A replacement for the invulnerability sphere that makes you scream at the top of your lungs while heavy metal blares in the background.
** An automatic shotgun that can launch a spread of empty shell casings.
** An automatic shotgun that can launch a giant, bouncing shell casing that spews hundreds of normal sized shell casings in all directions to the tune of 1812 Overture.
** The most powerful weapon of all is a beacon which drops a Hindenburg-sized (and shaped) nuke that falls to the tune of Ride of the Valkyries before exploding with enough force to potentially wipe out entire maps. Even the above-mentioned nuts.wad, with over 10,000 monsters, will have upwards of 8,000 of them killed in one blast if used right.
*** Naturally, the player is not immune to their own ordinance and they quickly become a greater threat to themselves than the enemies ever were.