So there was this FirstPersonShooter called ''VideoGame/{{Doom}}''. And there was this genre called the {{roguelike}}. And Kornel Kisielewicz decided to make Doom [[ExactlyWhatItSaysOnTheTin as it would be if it were a roguelike...]]

The result is a surprisingly effective translation of the Doom "feel" to a genre that is usually known for its slow, cerebral, and complicated gameplay. [=DoomRL=], as it is known, is a relatively simple and fast-paced game, with an emphasis on ranged combat as opposed to most roguelikes' melee focus. The monsters [[LudicrousGibs paint the ground and walls red]] as you riddle them with bullets, dismember them with chainsaws, and pulverize them with {{shotguns|AreJustBetter}}. Rocket launchers and explosive barrels create flaming balls of death that destroy walls just as easily as they kill you and your enemies. Only a few levels into the game you will be turning hordes of zombies into red goo.

By no means is the game easy, however. That horde of zombies is eager and willing to shoot right back at you, along with all the monsters you remember from the FPS, including their [[SoundCodedForYourConvenience iconic growls.]]

On February 28, 2012, version 0.9.9.6 was released, which marks some major updates to the game. [=DoomRL=] now has a full tileset by Derek Yu (you know, the VideoGame/{{Spelunky}} guy) that uses Doom-style graphics for everything (the original ASCII graphics are still available in Console mode), interface improvements, mouse support, and high quality audio upgrades to music and sound effects.

On March 19, 2013, version 0.9.9.7 was released, which added several new special levels (including recreations of classic Doom levels like Phobos Lab), added Dual-Angel challenges (where you combine two challenges into one), and Archangel challenges (extra hard versions of existing challenges), new Uniques, as well as general gameplay/balance tweaks and bug fixes.

The game can be downloaded for free [[http://doom.chaosforge.org/ here]]. In addition, there is a .wad for actual VideoGame/{{Doom}} that reasonably replicates the uniques and monsters to the FPS itself: [[http://forum.zdoom.org/viewtopic.php?t=37044 DoomRL Arsenal]].

Kornel is working on a SpiritualSuccessor titled ''Jupiter Hell''. It has a trailer on [[https://www.youtube.com/watch?v=YFXzY0AUsU4 Youtube]], and a Kickstarter campaign to fund development is on the way.

Compare VideoGame/{{Teleglitch}}.

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!!This game provides examples of:

* AdaptationExpansion: There's a ''lot'' of stuff that wasn't in the original. For example, the [[Manga/{{Hellsing}} Jackal Anti-Freak Hand Cannon]].
* AnimateDead: Arch-Viles, as always. [[spoiler:The Apostle that you fight at the end of an Angel of 100 run can also do this]].
* AscendedGlitch: The tactic of corner shooting was initially possible because of a GoodBadBug that made enemies unable to see the player around a corner while they came up to the player against the wall, thus allowing it to be as ridiculously safe a tactic as it is. However it became such an integral part of Doom RL play that the developers kept it in and consider it a mechanic of the game, while new additions and adjustments were made with corner shooting in mind.
* AwesomeButImpractical: Whenever you find an exotic/unique that's of a weapon type not utilised by the build you're running, as your build will render them less effective than the weapons utilised by your build, if not rendering them completely ineffective.
** The Napalm Launcher. On one hand, you're [[LavaAddsAwesome drowning everything in lava]]. On the other hand, [[DidntThinkThisThrough you're drowning everything, including powerups, items and the path to the exit, in lava]]. Get yourself a pair of boots that makes you immune to lava to go along with it however, and you'll avoid the most impractical part of the weapon while reaping all the benefits of most enemies not being immune to lava will bring with it.
** Also, the Acid Spitter. Twice as powerful as the napalm launcher (it does up to 100 damage!), but in addition to spreading acid around it can only be reloaded by walking around in acid for ten turns to scoop it back up, instead of using conventional ammo. The Lava Armor can only be repaired by walking around in lava and unlike the acid spitter it doesn't even reduce the damage to compensate, but offers insane protection against explosives.
** The Tristar Blaster. Lets you blow up absolutely everything in one turn, yes, but it chews up fifteen plasma cells per shot and you just have to guess where two of those explosions will be. Oh and each blast doesn't even do much damage.
** The Cybernetic Armor. It's a Unique armor with a 7 protection rating, nearly twice that of Red Armor, but once equipped, you cannot ever unequip it and it cannot be destroyed. Additionally, it does not self-regenerate like other "cursed" armors. So an unwise player equipping it can put themself in what is essentially a death trap, as the armor inevitably gets weared down and loses most of its protection, while they're unable to remove it for fresher armor. The armor is fully moddable by Technicians however, so a Technician with the right mods and enough investment in their Whiz Kid trait could make it into something extremely powerful.
* {{BFG}}: Yes, it's [[TropeNamer that one]].
** SerialEscalation: Thought the BFG was the biggest your guns could get? Think again. From version 0.9.9.2 onwards, with the adequate mods and one level of the Whizkid trait, you can make the BFG into the '''V'''BFG, which works like the Nuclear BFG, but packs even more of a punch than the regular one. What? Not satisfied yet? Don't worry, we've got the thing for you! With a bit more work and two levels of the same Whizkid trait, you can make the '''Biggest Fucking Gun''', which is ExactlyWhatItSaysOnTheTin.
* {{BFS}}: The [[{{Manga/Berserk}} Dragonslayer]], which renders you permanently berserk, and which receives a damage boost when paired with the Berserker Armor.
* BonusBoss: Any boss other than the Cyberdemon, the Bruiser Brothers, or the Spider Mastermind is one, since every other level with a boss is optional to complete.
* BoringButPractical: The tactic of corner shooting, which involves hiding behind a corner, and shooting at an approaching enemy as they come near, with a weapon that knocks them back. The corner keeps you out of their line of sight (thus they will not fire on you), and they'll keep coming back up against the wall until they die. This involves a lot of waiting in the same spot, and you can't use bigger weapons like Rocket Launchers, as they'll destroy your cover. However, this is the safest way to kill any enemy that's not immune to knockback without sustaining damage.
** Dual pistol builds. Pistols are, generally speaking, the weakest weapon in the game, but by the time you get to the point where you can fire two at once, you're also practically certain that every bullet will hit and deal a fair chunk of damage, and pistol ammo is everywhere, so you never have to worry about running out.
** The most consistently useful assembly in the game? Plain old Tactical Boots. They provide absolutely no protection to acid and lava whatsoever nor have any special effects. But all that is required to make them is a pair of Agility mods on a pair of common Steel Boots, which can easily obtain by the first few levels, while they provide a very valuable 15% boost to your movement speed. Since you can usually just avoid walking in harmful fluids, there's little downside to wearing them, leaving no reason to not wear them nearly all the time unless you're lucky enough to get boots with an even greater movespeed bonus. Pre-0.9.9.7 versions of the game even had them grant you a 10% bonus to your dodging rate, but Tactical Boots were deemed so ridiculously low cost and effective that the dodge bonus was removed.
* BrutalBonusLevel: Some Red Stairs lead to these (others are closer to BreatherLevel).
** The Mortuary and Limbo are the most infamous case: Five (or more, on higher difficulties) [[AnimateDead Arch-Viles]], and hundreds of randomly selected corpses (which could be anything from [[{{Mooks}} Former Humans]] to [[DemonicSpiders Mancubi]]).
** For those running Pistol builds, the City of Skulls, due to the insane amount of Lost Souls with their 50% bullet resistance, and Pistols generally being poor at fighting multiple enemies in the open (where City of Skulls has no cover).
** Entering Hell's Arena while still low-level may or may not result in this -- it depends on luck.
* ClassAndLevelSystem: As of version 0.9.9.4, you can choose among 3 different classes for your player character: The tanky Marine, the dodgy Scout and the resourceful Technician. Each with his own starting abilities and choices of master traits, as well as the ability to get a particular Advanced Trait (Which varies for each class) from the start without having to get other perks first.
* ChainsawGOOD: Not only does it deal incredible damage, you get a free berserk pack effect the first time you pick it up. It gets even more powerful with a piercing assembly and a good melee build.
* CharacterClassSystem: Version 0.9.9.4 introduces three character classes: the Marine, the Scout, and the Technician, each with their own starting perks and access to different traits/certain traits earlier than others.
* ConvectionSchmonvection: Lava does a lot of damage, but only if you run over it.
* ColourCodedForYourConvenience: Exotics, Uniques, and Artifacts bear respective purple, green, and yellow colors while on the ground, and will have the same colors when listed in the player's inventory. Unique versions enemies also have their own colors; in what might be a ShoutOut to [[VideoGame/{{Doom}} Doom 64]], the [[EliteMooks Nightmare variants]] of enemies appear dark blue.
** With the graphical update in 0.9.9.6, the same special items will have color-coded auras before they are picked up, extending to special armor that your player wears and is actually visible on the player's character in-game.
* CripplingOverspecialisation: Arachnotrons, in a sense. With their plasma guns and rapid-fire abilities, it's hard to tank or dodge them, but if you can get into melee range, they're practically helpless, and a melee build with a chainsaw or even a chainsword can one-shot them with ease.
* DesignItYourselfEquipment: Since version 0.9.9.2, certain combinations of equipment and mods can result in special equipment being created. Some of them are so-so upgrades for your normal gadgets of destruction, others are true behemoths that will help you greatly in raining fiery death on the hordes of hell. The more ranks you have in Whizkid, the more mods you can put on something and the better gear you can create.
* DeathInAllDirections: The [[FatBastard Mancubi]] launch three rockets - one directly at you, and two to either side. If you are along a wall when this happens, you may as well kiss your ass goodbye (though their rockets have been weakened in 0.9.9.7, eliminating the sudden one-hit kills that were common from them).
** The special weapon called the Tri-Star Blaster gives you an energy weapon version of the Mancubus attack.
* DegradedBoss / KingMook: On the Angel of 100 challenge, you can find most boss monsters in the lower levels as normal enemies, exceptions being the Arena Master, Angel of Death, [[FinalBoss Spider Mastermind]], and [[spoiler:[[TrueFinalBoss John Carmack]]]].
* DevelopmentHell: Despite Jupiter Hell being touted as a spiritual successor, Version 0.9.9.7 is not intended to be the final version of the game, and the developers stated the next version is in the works, while asking the forums for new things to add to the game. However, with Kornel focusing his efforts on Jupiter Hell, it's been over three years since 0.9.9.7's release, and there's still no sight of the next version's release. The originally planned sequel to DoomRL teased in the game's ending SequelHook also seems like it'll never come to fruition, with it never making it past a conceptual stage, and with the gameplay ideas that Kornel had for it being implemented into Jupiter Hell.
* DoNotRunWithAGun: When the player has the run command active, their shots will have about half the accuracy they normally would. Having the Scout's Gunrunner trait will prevent this penalty however.
* DoNotSpoilThisEnding: Anyone reading spoilers knows about the TrueFinalBoss, and the official wiki provides the full details on how to get a [[GoldenEnding full win]] instead of a standard win. However, a couple of the secret items, the Dragonslayer and the Berserker Armor, require the player to [[GuideDangIt meet specific conditions]] to pick up and use, and the few people in the community who have figured it out have all agreed not to reveal the secret. The same goes for the highest player rank, Apostle.
* DoomDoors: Well, it's ''Doom''...
* DramaticGunCock: You can go crazy with this, especially by pumping six rounds into the chamber of an empty tactical shotgun.
** Also, picking up or readying any weapon, including the combat knife, produces a cocking sound.
* DualBoss: The Bruiser Brothers, two buffed up Barons of Hell, at the Phobos Anomaly (formerly called the "Hellgate").
** In Deimos Lab, the player must fight two Shamblers at the end of the level.
* DualWielding: The Malicious Blades master trait allows you to dual-wield one-handed melee weapons with deadly precision and with a sizable defensive boost.
* DuelBoss: The showdown with the Cyberdemon, as per the original game. No mooks, no fancy tricks, just you against a T-rex sized demon lord with an [[Comicbook/{{Doom}} armful of rocket launcher and a head full of mad.]]
** The Spider Mastermind as well. [[spoiler:Unless you brought a nuke]].
** There's also the Angel of Death, which you fight in the Unholy Cathedral.
* EarlyBirdBoss: The Arena Master is pretty much an ordinary Arch-Vile. Who happens to be faced in a sidebranch from level 5. For reference, on normal mode Arch-Viles don't start showing up until level 16.
* EarlyGameHell: In the Angel of Berserk challenge (where you're restricted to melee weapons only), the game tends to be at its hardest early on, where the lack of equipment and levels really hurts a pure melee build, though the difficulty tapers off greatly once you get the Chainsaw and some levels with which to build your traits. This was especially bad in early versions of DoomRL, where the player didn't get a guaranteed Combat Knife at the end of the first level (and would thus have to go through the first two or so levels with just their fists).
* EasyModeMockery: On the easiest difficulty level, I'm Too Young To Die, some special levels cannot be accessed. Additionally, you cannot play any of the challenges on I'm Too Young To Die.
* ExplodingBarrels: It wouldn't be Doom without 'em. Most of them are just Fuel Barrels that simply explode and could take out doors or a wall if pushed near them. A later update introduced 2 more types of barrels, Acid and Napalm, that could leave Acid or Lava tiles after they explode. The latter must be that ''[[{{VideoGame/Contra}} Contra 3]]'' napalm.
** Some levels have levers that could have a number of effects when pulled; one of these is detonating all barrels present in a level at the same time. Which can be great if the resulting explosions damage or kill enemies...not so much if [[LostForever rare weapons/items get destroyed]].
* FisticuffsBoss: The Angel of Death, as the arena it spawns in, the Unholy Cathedral, only allows melee weapons. Piece of cake if you're specialized in melee, not so much otherwise.
** If the Doomguy has fast enough attacks and movement, it's possible to nibble the Angel of Death with fists or a knife without him having a chance to retaliate. When using a knife, this almost literally invokes DeathOfAThousandCuts - you'll be damaging him for 1HP per hit and on higher difficulties, he has over 400HP.
* GameBreakingBug: In version 0.9.9.6, a bug nullifies the effect of the Fireangel master trait. Normally this trait would make you completely immune to explosions, but in this version this trait is rendered completely useless (woe behold any player unaware of this glitch accidentally blowing themselves up after getting this trait). This bug was fixed in 0.9.9.7
* GetBackHereBoss: [[spoiler: [[VideoGame/{{Quake}} The Shambler]]]] in Hell's Armory and Deimos Lab, which teleports to lick its wounds in between shooting at you. Between its high HP, respectable Armor stat, resistance to explosions, and its innate regeneration, it can be a real bitch to kill before it kills you.
* GiantSpider: Arachnotrons, just like in the original - cybernetic demon spiders equipped with rapid-fire plasma cannons, and some of the worst foes to fight in a pack. As of version 0.9.9.5, the original game's FinalBoss, the Spider Mastermind, has made her return - and as might be expected, she's much worse than the Arachnotrons.
* GlassCannon: The Former Commandos. While they are armed with a Plasma Rifle even more powerful than the one used by Arachnotrons, their HP isn't much higher than the other former humans, and is much lower than the HP of all the demonic enemies besides Imps.
** The Doomguy can easily become this, when playing the Angel of Humanity challenge. The "glass" factor is present right off the bat, with only 10HP. The "cannon" factor comes in upon finding some decent firepower - if Doomguy survives long enough.
* GunKata: It's a Master Trait that gives you a free shot every time you dodge, and an instant reload every time you kill an enemy with your pistols.
** Taken further if you get this trait ''and'' you're lucky enough to find a [[Film/{{Equilibrium}} Grammaton Cleric Beretta]].
* {{Gorn}}: While it's no Dwarf Fortress, the gore is still impressive for a text-based roguelike.
* GunsAkimbo: The "Dualgunner" trait lets you shoot two pistols at once.
* HarderThanHard: [[ExcitedShowTitle Nightmare!]] Along with the standard respawning enemies this difficulty is known for, the [=DoomRL=] take on this cuts the player's speed by 10%, gives enemies an additional 50% chance of attacking, and prevents the player from saving. That exclamation point is there for a reason.
** That's not all! [[EliteMook Powered up, dark blue versions]] of these standard enemies will appear with a ''Nightmare'' prefix: Imps, Demons, Cacodemons, Arachnotrons, and Arch-Viles. The in-game description of Nightmare Arch-Viles likely mimics players' reactions upon seeing them: "Oh God... *WHY* do they come in the nightmare version too?"
** In version 0.9.9.7, there are now Archangel challenges, which take existing challenges and make them even harder. Enjoy such conditions such as having only two inventory spaces, having absolutely no source of healing outside the Vampyre mastery skill, and only having 10 HP while getting no benefits from levelling up.
* HighPressureBlood: You'd be surprised how messy an ASCII game can get.
** Played straighter with the graphical tileset introduced in 0.9.9.6.
* HoistByHisOwnPetard: The Arena Master will only be faced if you beat Hell's Arena earlier, which means he will only be faced if he already handed you a bunch of valuable items including a good weapon. On most runs those items include a rocket launcher and a bunch of rockets, which turns out to be an ideal weapon for fighting him.
* IdiosyncraticDifficultyLevels: Inherited from Doom.
* InfinityMinusOneSword: The Lance of Longinus is the second-most powerful melee weapon after Azrael's Scythe and the Dragonslayer. However in order to get it you must defeat the [[VideoGame/Wolfenstein3D Angel]] [[DuelBoss of Death]] in single combat - and restricted to melee weapons only. Hope you brought your chainsaw!
** InfinityPlusOneSword: Azrael's Scythe, as mentioned above, is the most powerful melee weapon in the game. The catch to get it? Like above, you must defeat the Angel of Death in single combat, and you can only use melee weapons. Unlike above, you must do it in, at least, Hurt Me Plenty difficulty. And you must have killed ''all'' enemies in your way to the Unholy Cathedral. [[EvilLaugh Hahahahaha]]! Good luck, '''sucker'''!
*** There's also the Dragonslayer, a weapon as strong as Azrael's Scythe, and when equipped, grants you permanent [[SuperMode berserk]]. However, it has secret conditions to finding it and being able to wield it.
* MagikarpPower: The pistol is the earliest and weakest weapon in the game, and better weapons become available very quickly. However, if you take a couple of levels in the "Son of a Gun" trait, you can become a "Dualgunner", which lets you wield and reload ''two'' pistols at the same time. Combined with the pistol prowess you gain from all these traits, the pistol suddenly becomes a surprisingly deadly weapon - and of course, you can still mod those pistols to make them even deadlier...
* MarathonLevel: The Angel of 100 challenge, which removes all the named and special levels, and makes you run through 100 randomly generated levels to win.
** [[UpToEleven Taken to the extreme]] in the Archangel of 666 challenge, where the player must descend 666 levels to win.
* MookMaker: Pain Elementals, which as per the original Doom spawn Lost Souls. New to this game are the Agony Elemental, which can spit out both Lost Souls as well as Pain Elementals, and the TrueFinalBoss [[spoiler:John Carmack]], who in addition to being as robust a tank as the Spider Mastermind, also has the nasty ability to summon eight mooks around itself at the same time. Depending on how hurt it is, they can range from measly Lost Souls all the way to [[EliteMook Barons of Hell, Mancubi and Arachnotrons]].
* MoreDakka: The usual suspects such as the Chaingun (and its upgrade, the Gatling Gun) and Plasma Rifle are here, but the BFG 10K takes the cake. In addition to the standard weapon, with the Bullet Dance master trait a Marine class character can rapid fire with his pistols and take full advantage of both Son of a Gun and Son of a Bitch damage.
* MultiMookMelee: A recent update introduced "Single Monster" levels that can result in one of these. The level will be populated entirely with a certain monster type, which is indicated by the 'Feeling' the player's character has when entering.
** If the game is feeling extremely cruel, there's 10% a chance that the level will be filled entirely with [[DualBoss Bruiser Brothers]], [[spoiler: [[VideoGame/{{Quake}} Shamblers]]]], or even '''[[OhCrap Cyberdemons]]'''. Hope you got one of those Homing Phase Devices with you.
* MultipleEndings: There are three ways to win DoomRL. [[spoiler:The first is by killing the Spider Mastermind, which requires either killing her normally or using a Thermonuclear Bomb on her. If you do the latter without some means of surviving the blast, you're said to have sacrificed yourself. If you have a means of surviving the blast, you get to go fight the TrueFinalBoss. Losing to him is considered roughly the same as sacrificing yourself, but if you defeat him, you will get a full win.]]
* MythologyGag: The TrueFinalBoss [[spoiler: John Carmack]] is named after one of Doom's developers, and the fortress you meet him in is [[spoiler:a giant ''Creator/IdSoftware'' logo]]. In addition, the Bruiser Brothers, a pair of unique Barons of Hell guarding the Phobos Anomaly, are named after the original pair of Barons that appeared at the end of Doom Episode 1.
* NintendoHard: Much like any other roguelike, [=DoomRL=] can get murderously hard, particularly if you're on Ultra-Violence or Nightmare.
* OhCrap: If you see the message "Suddenly you have a great urge to turn back! You scream in TERROR!", it means that [[spoiler:every single enemy in the level has been replaced by a Cyberdemon, which most likely means unless you are very, very lucky, good or both, you can kiss your run goodbye]].
** There's also the message you get if you're unfortunate (or stupid) enough to hit a lever that floods the entire level with lava: "Oh shit, oh shit, OH SHIT!!!!"
* PlayerNudge: Finding the TrueFinalBoss requires some careful combination of rare or hard-to-find items. However, the most common of those items, thermonuclear bombs, contain a big hint in their description. And after you beat the normal FinalBoss, if you look carefully at the post-mortem for your character (particularly after [[TakingYouWithMe nuking him]]), the final screenshot will provide a big hint.
** Beating Angel Of 100 mode gives a hint that you missed doing something that had some relation to the Dragonslayer secret.
* PublicDomainArtifact: The Longinus Spear.
* RareGuns: A lucky player may find guns like the Pancor Jackhammer or a Minigun, or even rare ''fictional'' guns like the aforementioned [[Manga/{{Hellsing}} Jackal]].
* RPGElements: You get to pick a "trait" every level, which have effects ranging from "more HP" (Ironman) to "reload your shotgun while you move" (Shottyman).
* SecretLevel: There are "special levels", signified by their entrances having red stairs, that are completely optional for entering and completing for a standard win. These levels are non random (or have a few spots of specific randomness) with a gimmick that the player must overcome (such as Hell's Arena having three different waves of enemies the player must defeat), often having a boss at the end, and great rewards for the player should they complete the stage. In difficulty, they run the gamut from BreatherLevel (Halls of Carnage), to BrutalBonusLevel (The Mortuary and Limbo), to being [[UnwinnableByDesign unwinnable]] if the player did not come into the level with the required items (The Wall), though in this case, unwinnable just means the player can't get 100% kills and the level's max reward. The difficulty of a special level can also greatly depend on the build a player is running (City of Skulls is a BreatherLevel for Shotgun and Berserker builds, while being a BrutalBonusLevel for Pistol builds).
* SequelHook: The game's ending outright states there will be a "DoomRL 2: Hell on Earth", implying the demons made it to Earth as in the original Doom 2. However, as covered in the game's aforementioned DevelopmentHell section, it seems like it'll indefinitely remain VaporWare, with the developers instead deciding to make an original IP they could profit from, with whatever conceptual ideas they had for the sequel being used for Jupiter Hell.
* ShootTheMedicFirst: Archviles have the power to revive dead enemies. 'Nuff said.
* ShortRangeShotgun: The Combat Shotgun is reasonable, but the Double Shotgun is obscenely short-ranged.
* ShockAndAwe: [[spoiler:[[VideoGame/{{Quake}} The Shambler]]'s]] main attack consists of hurling lightning bolts at your soon-to-be-fried Marine.
* ShoutOut: Some of the traits are headed by quotes from the infamous [[Comicbook/{{Doom}} Doom comic]]; many of the unique weapons such as the [[Film/{{Equilibrium}} Grammaton Cleric Beretta]] or the [[VideoGame/QuakeII Ra]][[VideoGame/QuakeIIIArena il]][[VideoGame/QuakeIV gun]].
** [[VideoGame/DwarfFortress BLOOD! BLOOD FOR ARMOK, GOD OF BLOOD!]]
** ''"[[Literature/TheChroniclesOfAmber In the state of Denmark there was the odor of decay...]]"''
** VideoGame/QuakeI's Shamblers make an appearance, this time, as bosses. And as with Quake, they're resistance to explosives. They also seem to have taken a page from Lovecraftian Dimensional Shamblers (which were alluded to in an Exit to DOS taunt in the original Doom), because they can teleport at will, making it impossible to run from them, and making cover unreliable.
** Speaking of ''Quake'', Quake 2 and 4's Hyperblaster make an appearance.
** One of the several special levels is called TheWall, which naturally ends with this upon exiting after clearing the area of all enemies: "[[Music/PinkFloyd All in all, we're just another brick in the wall.]]"
** The Storm Bolter and Burst Cannon from TableTop/Warhammer40000 make an appearance.
** The Jackal, [[Manga/{{Hellsing}} Alucard's personal weapon of choice]], is one of the unique pistols.
** As well as the Manga/TriGun.
** One weapon is the Mega Buster. VideoGame/{{Mega Man}}s ArmCannon.
** One "weapon" is the [[Franchise/{{Unreal}} combat translocator]], and works exactly as in that game.
* SkippableBoss: Surprisingly, the Bruiser Brothers can be skipped by just running into the portal they're guarding without killing either of them. Doing so all but requires getting lucky with a phase device however, and even then the terrain is narrow enough that you'll take some hits.
* SoundCodedForYourConvenience: Very important, since there's many things which have audio cues but no visual ones (most importantly hitting an enemy who is out of sight without killing them, enemies using healing items or teleporting, enemies reloading their guns and sounds which indicate that each type of demon is nearby). Playing without the sound on would be difficult indeed.
* StandardFPSGuns: The exact lineup from Doom II along with a knife and a combat shotgun, along with some additions.
* SuperMode: Berserking. Doubled melee damage, 60% reduction in damage taken (''before'' applying armour!), and all your actions are faster (in an unintuitive, historically quite buggy, and still slightly glitchy way).
* TakingYouWithMe: You can find thermonuclear bombs along the way. Setting one off on the final boss's level will give you a "partial win". Of course, if you find a way to [[GuideDangIt live through]] [[OutOfTheInferno the explosion]]...
* ThereWasADoor: This happens sometimes, mainly because of the aforementioned ExplodingBarrels and rocket weapons.
* ThirteenIsUnlucky: On Phobos Anomaly, taking exactly 13 steps east from inside the first doorway will trigger a large ambush.
* TimedMission: Invoked with the aforementioned Angel of Red Alert challenge that places a 5 minute Thermonuclear Bomb (about 240 ingame seconds) on each level. With a recent update, the same can now occur randomly in a standard game, but with an 8 minute nuke.
** This is amp up farther in the Archangel of Red Alert challenge, where each level has a 2 and a half minute Thermonuclear Bomb set.
** There's also the Halls of Carnage, which fills with lava over time. The same occasionally happens on normal levels at random but is much slower when it does.
* TooDumbToLive: Pinkies and their Nightmare variant will run through an open pool of [[LavaPit lava]] or [[HollywoodAcid acid]] if it happens to be between them and the player, despite them having no immunity nor resistance to harmful fluids. Savvy players can exploit this to take them down easier, especially at low levels when they lack the firepower to take them down easily. All other enemy types are smart enough to avoid fluids unless they can fly over them or are immune to fluids, and will immediately get out of a pool of fluid if they're knocked into it.
* TookALevelInBadass: Literally! Putting a point into the Badass trait reduces knockback and prevents HP above 100% from decaying.
** Less literally, the best traits require you to first learn other traits to learn them, which may not be quite as useful by themselves.
* TrueFinalBoss: If the player [[spoiler:nukes the Spider Mastermind and survives it by possessing invulnerability, they'll gain access to one more level called the Hell Fortress, where they'll fight the true final boss, John Carmack. Defeating him is required to achieve a "full win".]] Pre-0.9.9.2 this was a LuckBasedMission that required the player [[spoiler:to find a randomly-generated nuke in their playthrough and find a randomly-generated invulnerability sphere close enough to the last level]], but in recent updates, guaranteed items obtained through the bonus levels can allow the player to achieve it every playthrough.
** The game has another secret final boss: [[spoiler:If the player makes it to the Hell Fortress with the Dragonslayer and Berserker Armor equipped, John Carmack will be replaced by the Apostle, a ridiculously overpowered Archvile that can teleport. The Apostle will also appear on the last floor during the Angel of 100 and Archangel of 666 challenges if the player has the aforementioned equipment.]]
* UnwinnableByMistake: On the Angel of Overconfidence challenge, it's possible to spawn in an Arachnotron cave on the first level while surrounded by Arachnotrons, where due to lack of traits and items, as well as sufficient weaponry/armor, will get the player killed before they can even fight back, as can be seen in this [[http://forum.chaosforge.org/index.php/topic,5367.0.html mortem]].
* YetAnotherStupidDeath: It's a roguelike; there are plenty of these to be had. [[LampshadeHanging Lampshaded]] in the post-mortem text if you blow yourself up or take a lava/acid bath.
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''As you descend the stairs you hear a wail. They're back... There's only one way to end this...''
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