Warhammer 40,000/Tropes/I to P

By the will of the Immortal God-Emperor, the great reliquary, or "page" as it is known, of tropes has grown to the point that it shall be broken up into three different pages. These pages are divided by the letter that starts the trope, and misplaced tropes shall be returned to their proper place. This page is for those tropes that start with the letter I through the letter P.

Venerate the God-Emperor. To deep-strike back to the main page, click here.

I

 * I Did What I Had to Do: At least the "good guys". The bad guys just enjoy their work. The kicker? For the sake of surviving, they really DO have to do it.
 * I Don't Like the Sound of That Place: By the dozens. "The Eye of Terror" stands out the most.
 * If You Kill Him You Will Be Just Like Him: Quite literally. Anyone who kills Lucius the Eternal transforms into him and gets possessed by him.
 * I'm a Humanitarian: Soylent Viridians, a form of food ration, also referred to as "corpse starch."
 * There's also a widely known and somewhat popular religious sect whose main gimmick is cannibalism, though this behavior is generally frowned upon by the Ecclesiarchy as a whole.
 * The Kroot have this as their hat, as when they eat something they incorporate parts of its genome into their reproductive DNA. They began as vultures scavenging ork corpses and eventually became a bipedal, if still distinctly avian, species that eats their own (and everyone else's) dead, if the individual was strong enough to warrant being incorporated into future generations.
 * Tyranids are the same, except that they're an entire species dedicated to consuming organic matter (even their own) and use biological weapons to the exclusion of all else (so they can "recycle" spent ammunition later).
 * Blood Angels and their descendant chapters are this under the influence of the Red Thirst. Some chapters like the Flesh Eaters and the Flesh Tearers even have it right in their names.
 * Immortality Inducer: The Emperor's throne.
 * Immune to Bullets: Big daemons and monsters are generally more or less proof against small arms, though not against heavy weapons.
 * The Dark Eldar have Grotesques, crazed BDSM fans who have turned upon their own bodies. Their special rule lets them ignore all shooting attacks with a Strength of 5 or lower. They have 2 wounds. Yeah. (They only die from shooting attacks which would automatically kill them anyway. Nothing short of weapons designed specifically for punching through tank armor will drop a Grotesque.)
 * Armour Value 14. Especially the Monolith.
 * Currently only the Wraithlord, Talos, Cronos, Monoliths, and Land Raider Variants are able to actually completely ignore mainstream shooting (and, in the case of the Wraithlord, close combat too). This is due to the To Wounds chart disallowing you to wound something with a Toughness value 4 higher than your Strength Value. Same goes with Vehicles, where it is not allowed to penetrate something that has a AV 7 points higher than your strength (you're suppose to roll a dice and add it to your strength to see if you penetrated the enemy's armour, so by default 7 higher would mean it's nigh impregnable to you). This mechanic makes it so that Vehicle hunting weapons are actually a viable method and alternative to otherwise mono-purposed sniper rifles for taking down such beasties.
 * Impaled with Extreme Prejudice: Sometimes Frequently on a chainsaw.
 * Imperial Stormtrooper Marksmanship Academy: Orks + guns = hilarity. Fortunately, they have More Dakka where that came from. Averted with the Imperium of Man's own Storm Troopers, who can aim just as well as any Space Marine.
 * Implacable Man: Things like higher-level Tyranids, Space Marines, Orks and Daemons are ridiculously hard to take down, but the Necrons really take the cake.
 * Implausible Fencing Powers: In the spin-off game Inquisitor, characters are able to take a talent called "Deflect Shot" which allows them to attempt and deflect any shots fired at them as long as they are armed with either a power weapon (a melee weapon surrounded by a matter-disrupting energy field) or a force weapon (which is psychically linked to its wielder). This is also demonstrated in the last book of the Eisenhorn trilogy.
 * Although, in an odd case of quasi-realism, when somebody else does this in Ravenor, Harlon Nayl's answer is to switch to full auto and shoot her to bits.
 * Improvised Weapon: All Ork equipment is basically improvised out of bits of scrap metal. Even spaceships, because...
 * It Runs on Nonsensoleum: Ork technology is a justified case of this.
 * I'm Your Worst Nightmare
 * Incorruptible Pure Pureness: The Grey Knights, a Space Marine Chapter that serves as the military arm of the Ordo Malleus specializing in anti-daemon combat. In over ten thousand years of service, not a single one of their number has ever defected to Chaos. More impressive when you consider that at least half of all Space Marines had done so by the end of the Horus Heresy, which occurred somewhere around one thousand years after the Legions were created, and that Grey Knights are all psykers (and thus inherently more vulnerable to daemonic corruption).
 * Infernal Retaliation: Only mentioned in relationship to Tyranids, but more than likely applies to Necrons and Orks as well.
 * Inherent in the System: Were the oppressive and xenophobic Imperium of Man to ever fall (or even undergo significant reorganisation), the resultant chaos would lead directly and rapidly to Mankind's extinction at the hands of its many, many enemies.
 * Except of course against the Tau who would be more than happy to welcome more Gues'va into their empire, whether the humans were willingly or not.
 * Initiation Ceremony: Space Marines, especially the Grey Knights; also Chaos.
 * Insane Troll Logic: The whole premise behind Orky technology. Of course, since things tend to work if they believe it does... For example, vehicles go faster because they're red.
 * Intangible Man: Necron Wraiths.
 * Interservice Rivalry: To the point that rival Imperial Guard regiments, Space Marine chapters, Inquisitorial task forces, or any combination of the above will occasionally often open fire on each other in the name of the Emperor.
 * In the Name of the Moon: Every faction has their own equivalent.
 * Insectoid Aliens: The Tyranids and the Vespid.
 * In Working Order: Justified for Orks - if they think it'll work, it will, even if it's actually broken. Averted and avoided by everyone else.
 * It Got Worse: And how! The 5th Edition of the game has taken this even further, fleshing out the history of the past few hundred years - the Time of Ending - and revealing just how monumentally screwed the Imperium actually is. Although, given this is 40k, with loose ends such as, it's unlikely any faction is going to gain total victory.
 * It's Raining Men: Deep Strike.

J

 * Jack Bauer Interrogation Technique: The "Nine Actions" are the Inquisition's specific guidelines on gradually increasing the intensity of their questioning, psychological manipulation, torture, and Mind Rape. Action Nine would kill any normal human pretty quick, but then normal humans usually give in at about the two-mark, which involves explaining exactly what is going to happen through the next seven stages.
 * Dark Eldar are also adept at this, owing to their experience with torture in general. Generally, however, they're more interested in the captive's screaming than in any information he might have to offer.
 * The fate of any of the Fallen who survive getting captured by the Dark Angels. If they 'repent' they're given a Mercy Kill.
 * Jack of All Stats: Space Marines, especially the Ultramarines.
 * Jeanne D'Archetype: The Sisters of Battle are obviously based on Joan of Arc.
 * Jet Pack: Assault marines, Chaos raptors, Seraphim, Rokkit Boyz and Crisis suits.
 * Jerk with a Heart of Gold: Rowboat Girlyman Roboute Guilliman, primarch of the Ultramarines. Sure he could be an ass, but he legitimately cared about the people. His actions and policies would eventually lead to the Ultramar system becoming one of the nicest (and least corrupt) places in the Imperium.
 * Though he cared far less about people who didn't follow the Ultramarine example, such as when he killed an entire city as a warning to his brother Lorgar after Lorgar taught them to worship the Emperor, which Guilliman didn't like.
 * Join the Army They Said: The Imperial Guard.
 * Or, to quote 1d4chan, "Join the Imperial Guard or die. Then die."
 * Judge, Jury, and Executioner: Several organisations and individuals with this power. The Adeptus Arbites who enforce Imperial law (and who rather resemble the Judges of Mega City One, although this is superficial: according to Dark Heresy, abandoning due process and using summary execution is the worst heresy an Arbites officer can commit), the Commissars of the Imperial Guard, the Ecclesiarchy (who tend to favour unusual punishments) and, of course, the Inquisition. Innocence proves nothing.
 * "A plea of innocence in my courtroom is guilty of wasting my time. Guilty."
 * Unusual punishments...or Kill It with Fire.
 * The Juggernaut: Necrons, Tyranids, and the Imperial Guard Space Marines. There's also a breed of Khornate daemon actually called the Juggernaut; for the uninitiated, it's the thing that looks like an angry metal rhino.
 * Julius Beethoven Da Vinci: The Emperor is likely to have been Alexander the Great (his flagship is called the Bucephalus), among numerous other historical figures (or at least stole their stories to ease his transition to power).
 * Just Eat Him: What the Tyranids do.
 * Just Plane Wrong: As it's prone to doing, Warhammer 40000 takes this Up to Eleven; depending on the source, those stumpy Imperial fighters with leading edges a scale foot thick and bombers that look like the bastard offspring of a B-17 and an Abrams are single step to orbit spaceships which are just as at home fighting in the vacuum of space as they are in atmosphere. Even whatever this is can hit escape velocity, because air resistance is heresy.
 * Most are modeled to resemble WWII propeller fighters but with jets instead of propellers, yet they supposedly can achieve speeds in excess of Mach 2. Take the Imperial Navy's air fighters. Real world aerodynamics would conspire to prevent this (though ridiculously tough 40K materials in turn would conspire to prevent real life aerodynamics); though enough brute force can make anything fly, it has rather greater trouble making anything turn (you don't put the engine in the front in supersonic fighters, because it moves the Center of Weight fore of the center of pressure, and would make the fighter so stable in supersonic flight that no amount of control force would allow it to maneuver). Let's not even get started on the Orks, Chaos and Dark Eldar aircraft, this entry would reach monstrous proportions (well, more monstrous then it already has). The only aircraft that could maybe fly, and that's a very big maybe, are the Eldar and Tau. And that excludes that Tau dropship that looks like gussied-up cinderblock, obviously.
 * The Ork planes don't fly because they make sense, they fly because the Ork themselves think they can fly, in the same manner their trukks run faster when painted red.
 * Also, let's hear it for the Thunderhawk, an SSTO troop transporter with a scale 16-inch spinal gun that isn't under any kind of faring and is only capable of firing above the aircraft. This along with the slender midsection presumably makes the Thunderhawk the only troop aircraft to be able to land infantry in two places at the same time.
 * It's probably worth remembering that the Imperials, Eldar and Tau have anti-gravity technology, and the last two make extensive use of it. It's probably safe to say that this technology negates the need for aerodynamic structures somehow.
 * Eldar and Tau are not so big offenders. And while the Imperials use anti-gravity technology the fluff for the last three editions clearly states that it's used only} on the Land Speeder. Besides no amount of anti-gravity will prevent air-resistance, and the problem with Imperial aircraft is that they are not streamlined enough to reach their Mach 2+ maximum velocities given in fluff.
 * It's explicitly, primarily used on the Land Speeder...
 * Valkyrie can hover, but doesn't look like it either has takeoff engines for VTOL (like the nose thrusters on Thunderhawk) nor like its big engines could bend vector thrust this much (like a convertoplane). Antigravity? But if you look into details, there are also questions like "why the multilaser would be limited to powerpack, if there's clearly enough of power on board to recharge?" and so on.

K

 * Kick the Dog: Everyone, to everything, all the time.
 * Kill'Em All: This one was a no-brainer.
 * Killer Rabbit: The Catachan Barking Toad, a large, sad-looking amphibian sometimes dubbed the "Ronery Toad". If attacked, hurt or even surprised, it explodes into a cloud of obscenely virulent toxins, killing absolutely everything in a kilometer-wide cloud of death and poisoning the earth so that nothing will ever grow there again (yet somehow does not create clearings in Catachan jungles at the same time... sigh...).
 * Kill It with Fire: Imperial government policy towards everything. The Salamanders chapter of Space Marines and the Witch Hunters specialize in fire based weapons. The Sororitas are also very fond of flame-based weaponry. On the Eldar side, the Fire Dragons kill tanks with fire, specifically with fusion guns and firepikes.
 * Killed Off for Real: GW's Old Shame, the Squats.
 * Also Eldar special character Eldrad Ulthran, who made a Heroic Sacrifice at the end of the 13th Black Crusade global campaign.
 * And Blood Angels Captain Erasmus Tycho, who first was afflicted with the Black Rage, then killed, in the Third War for Armageddon.
 * King in the Mountain: The Emperor, several primarchs. Or so it is said.
 * Klingon Scientists Get No Respect: Ork weird boyz.
 * Knight in Sour Armor: The literature of Warhammer 40K has given us fairly decent people (for a given value of decent) who even in the face of all this madness keep trying to do what's right (for a given value of right... it's that kind of place). But next to none of them have any illusions that they'll actually succeed in the end, and only continue their works because it is their duty.
 * Knight Templar: Considered an ideal in the Imperium.

L

 * Large and In Charge: Orks actually get steadily bigger as they gain more authority, Chaos Lords who have ascended to daemonhood tower over their merely giant minions, and the size of Tyranid "Synapse Creatures" leads to one piece of advice in dealing with Tyranids: "SHOOT THE BIG ONES!". Also the manifest gods of the Necron race - C'tan - have a special rule called "Above All Others" on the battlefield, which is pretty self-explanatory.
 * Large Ham: Given how many characters are batshit insane, and how insanity tends to feel good in this setting...players who don't treat the game as Serious Business tend to get hammy as time goes on.
 * Laser Blade: Most power weapons are a disruption field-based variant of this, but a couple of genuine laser swords have come up in the fluff.
 * Laser Sight: Tau markerlights are a variation of this, and they also appear on a lot of Imperial Guard weapons. Some unkind players suggest that Imperial lasguns are laser sights; while they can remove a head or limb with a single shot, compared to the other weapons...
 * How do you twin-link a lasgun? Put a laser sight on it..
 * An Ork Targita or Gitfinda can be a crude version of this.
 * Last Stand: At any given moment, somewhere in the galaxy, an Imperial force is being wiped out to the last man. "The blood of martyrs is the seed of the Imperium."
 * Lawful Stupid Chaotic Stupid: Plenty of examples of both.
 * Law of Chromatic Superiority: Da blue wunz iz lucky, and da red wunz go FASTA!
 * Law of Inverse Recoil: Averted - firing an Autocannon has been known to break bones in an ordinary human, while Imperial missile launchers have been stated to have no recoil when fired correctly.
 * In 2nd Edition, Wazdakka Gutzmek (an Ork mekboy) rode a motorcycle that mounted a battle cannon, a fairly large tank cannon. The recoil would knock his bike back several yards every time he fired it.
 * Bolters are a strange example, and have many inconsistencies. They would actually be a lower recoil weapon than a traditional projectile weapon due to the bolts being self propelled; some publications have them with little recoil while others demonstrate massive recoil for the imagery.
 * Lean and Mean: The Dark Eldar.
 * Legend Fades to Myth: The setting is full of this.
 * The Emperor was not a god, half his campaigning was in order to eliminate the concept of religion (and one of his children turned against him because he ordered him to stop worshipping him). These days, he's the central figure of humanity's state religion.
 * Many of the more primitive worlds ascribe Space Marine landings as the God-Emperor sending his Angels of Death, sometimes the Marines looking for initiates are remembered as selecting the worthiest to live with them in paradise.
 * Lethal Joke Character: The Apocalypse expansion includes rules for a Warlord Titan, four times the size of the biggest model they actually sell with the point cost of an entire army and almost certainly meant as a joke. Then some people actually scratch-built them, and they are so unbalanced that an equivalent-cost force of super-heavy tanks and artillery can't even get through the shields before being wiped out.
 * And if that's not enough, one of the datafax on the Games Workshop website is for the Emperor Titan, which is best modeled by someone dressing up as the Titan and climbing on the table. It's all fun and games until someone's whole army gets squished....
 * To demonstrate, here is an official Reaver-class Titan miniature on scale with other 40k models. Here is a custom-built Emperor-class Titan in the same scale.
 * The Library of Babel: The Black Library.
 * Lighter and Softer: BrightHammer 40k. For starters, the Emperor is rocking a goatee, Slaanesh is all about love & kindness instead of sadism, and there is such a thing as peaceful diplomacy with Orks.
 * 4e showed some signs of this, as did the introduction of the Tau back in 3e. It Got Worse.
 * Arguably, the series was at its worst in the third edition. I joke not. During 3e, there were chaos cultists on Terra, the Imperium was losing worlds by the hundreds and High Lords did not care, in fact most of them had been driven insane by imperfect deageing treatments. This was before the Horus Heresy, before the Imperium's methods were justified by dozens of books. There was no Ciaphas Cain, no likeable or sane character to be found. The Sisters of Battle fielded suicide bomber cadres, the Space Marines were a shadow of their power in latter editions, and even more insane: imperfections in their half forgotten surgical techniques rendered 9 out of 10 recruits dead and the survivors deranged. The Religious Horror was at its peak, the artwork like of things that can barely be called human hugging and kissing undetonated artillery shells, begging the gods of war for salvation has never been reprinted, the forces of Chaos, later Ultimate Evil, were simply presented as a alternate form of insanity to that of the Imperium's. By 5e, Warhammer shows an Age of War where humanity's survival hangs in the balance. 3e showed an Age of Insanity where the spirit of man was long dead.
 * Tales of the Emperasque has this mixed with Bloody Hilarious... and it's a Crack Fic deconstructing Deus Ex Machina, no less.
 * A Lighter Shade of Black: Probably the reason why many players still prefer to stick with the Imperium. And to a lesser degree, the Tau and Eldar.
 * Light Is Not Good: The Church Militant makes sure of this one.
 * Lightning Bruiser: Necrons exhibit shades of this on the ground (assuming they make full use of their monoliths and other fast-moving troops), but their naval fleet really takes the cake.
 * The commanders of many armies are wicked fast in combat, orders of magnitude tougher than basic infantry, and often capable of wiping out entire squads of enemy troops single-handed in melee.
 * A fair number of armies' units in the first place. Space Marines in particular are consistently noted as being more agile than anyone would expect given their bulkiness and mass.
 * Lightning Gun: Laser-ionization type (unsurprisingly, given the Imperium's love of lasers). One of the old (30k era) designs. Has Charged Attack. And then there are Lightning Cannons sized for a tank (of course).
 * Luminen Blast is Tesla Coil style (unsurprisingly, given Mechanicus Mad Scientist inclinations) short-range discharge possible with bioelectrical Mechanicus implants - not energy-efficient, but any attack that stuns has its uses, let alone ranged one. And of course, some Techpriests really take it to the heart and go on a merry rampage...
 * Limited Wardrobe: If the artwork and models are anything to go by, every single female Death Cult Assassin in the Imperium (and we've yet to see a male one) wears the same slashed-up bodyglove, the same skull-decorated corset, and the same high-heeled boots, and is armed with either the same katana or the same pair of daggers. And nine times out of ten, they'll be wearing the same gimp hood and have the same bionic eye, to boot.
 * Living Labyrinth
 * Living Ship: Tyranid vessels. Eldar vessels are living in a way; some even have no crew, being piloted solely by the spirits of the dead.
 * Lizard Folk: Loxatl are lizardmen amphibian-men that are very resistant to lasgun fire and have weapons that would be very nasty in any other setting. There are also the Slann, the Recycled in Space version of Warhammer Fantasy Battle Lizardmen, though they don't show up much in the fluff anymore.
 * Loads and Loads of Rules: Rogue Trader's comically huge rulebook, and Second edition's obsession with insanely complex special rules. Just try firing a Conversion Beamer or Thudd Gun without having to consult the rulebook repeatedly.
 * The Imperial Robot rules in Rogue Trader were probably the most complicated set of rules for a single model in the history of the game (though the Imperator Titan and Mega-Gargant come close). Basically, any time they wanted to use a Robot, the player would have to create a program for it before the game started using a series of logic gates to define how it would react to various situations (no visible targets, target in sight but out of range, target in sight and in range, etc), with the robot's points cost being partly decided by the number of instructions in its program. This was about as complicated and pointless as it sounds, and might well be the reason the later editions avoided the idea; the Legio Cybernetica seemed to go the way of the Zoats and Squats.
 * Look on My Works Ye Mighty and Despair: The Eldar and pre-Imperium humanity. Also the Necrontyr - precursors to Necrons - have achieved an incredible level of technological advancement before turning their souls over to C'tan and becoming the legion of killer robots that held the entire galaxy in their sway, but then of course something even worse came along in the form of Enslavers.
 * Looks Like Cesare: Astropaths, due to their Soul Binding.
 * Loophole Abuse: When the rules of the Ecclesiarchy were rewritten following the Age of Apostasy, the Imperial Church was prohibited from maintaining any "men under arms," so as to avoid the wanton abuses of power that characterized the reign of the previous Ecclesiarch. The rule was intentionally worded this way so that the Ecclesiarchy could maintain the Sisters of Battle as an internal police force.
 * Losing the Team Spirit: Killing the Tau army's Ethereal has this effect. Either it breaks their morale, sending them fleeing, or causes them to go on a Roaring Rampage of Revenge, gunning down any enemies on their patch.
 * It should be noted that such Unstoppable Rage among the Tau typically takes the form of a slow, steady advance as the Fire Warriors methodically pour shot after shot into the enemy until they are killed, the enemy is killed, or they run out of ammunition.
 * Lost Colony: All over the place.
 * Lost in Transmission: Imperial vox systems are notorious for going on the fritz when they are needed most. This is lampshaded by a Silver Skulls chapter marine in one of the books, when he muses on the likelihood of a civilization that can genetically engineer Super Soldiers being unable to create reliable comm systems.
 * Lost Technology: See also Cargo Cult, Ancient Astronauts, Sufficiently Advanced Alien and Sealed Evil in a Can. The Blackstone Fortresses come under all five.
 * Loves the Sound of Screaming: The Dark Eldar.
 * Low Culture, High Tech: Orks and Humans, due to the various scavenged and Lost Tech.
 * Luck Manipulation Mechanic: In the Warhammer 40000 Trading Card Game, numbers are printed on the cards, so a 'random' number is generated by revealing the top card of your deck. Naturally, this opens up plenty of combo opportunities with abilities that let you know (or even choose) what that next card will be.

M

 * Machine Worship: The Adeptus Mechanicus first and foremost, but also the Iron Hands chapter of Space Marines.
 * Macross Missile Massacre: Sisters of Battle Exorcists, huge gothic church organs mounted on the backs of tanks, which fire anti-tank missiles as the battle nun in her armored cockpit presses the keys. 40k, quite literally, pulls out ALL the stops.
 * The Tau have the Skyray Missile Gunship, which comes equipped with smart missile system clusters, and a rack of larger Seeker missiles, which are fired remotely by troops behind the lines.
 * The Apocalypse Missile Launcher. That is all.
 * Terminators can mount something called a Cyclone Missile Launcher. Not only does it allow said Terminator to fire it and his Storm Bolter (a rapid-firing RPG launcher), the Cyclone Missile Launcher itself fires twice as fast as a normal Missile Launcher.
 * In Second Edition, rather than simply firing twice per round, the Cyclone came pre-loaded with twelve krak missiles, and the Terminator carrying it could launch any number he wanted at a time: meaning, if he wanted, he could trigger all twelve at once for a truly Macross-y rain of death. However, the Cyclone was also prone to potentially disastrous misfires if the Terminator carrying it was hit.
 * Mad Oracle: Precognition is a fairly well-known power of psykers, but carries with it The Dark Side. Aside from the Eldar, The Dark Side seems to win more often than not with would-be prophets.
 * Mad Scientist: A great many Imperial tech-priests fall into this, though arguably all tech-priests are insane by modern standards - and those of them who "go too far" by their standards (wind up branded Hereteks and hunted down) tend to be far crazier. Non-Imperial examples include Fabius Bile, Dark Eldar Haemonculi, and Ork Painboyz and Mekboyz (also known, appropriately enough, as Mad Doks and Mekaniaks respectively).
 * Made a Slave: All sorts of people. Orks enslave, Dark Eldar enslave, Chaos forces enslave: even Imperial Space Marines have slaves to do work that a Space Marine is not needed for (though the Marines' slaves are generally failed Marine candidates who somehow survived washing out, and are often more than happy to help, since they're still in a better position than the vast majority of Imperial citizens).
 * Imperial propaganda paints humans who join the Tau Empire as this, while the Tau propaganda paints them as becoming freed from the miserable existence of the Imperium. The actual result is likely somewhere in between, though which side it leans more toward varies on a case-by-case basis.
 * Made of Iron: Many, many people, ranging from nigh-invulnerable Space Marines like Marneus Calgar and Captain Cortez (who has exactly two bones in his entire body that have never been broken, and once led a charge with a broken back), to Ork Warbosses, to powerful Daemons, to Commissar Yarrick, who takes a lot of effort to permakill.
 * Made of Plasticine
 * Magic Is a Monster Magnet: Psykers risk having their brains eaten every time they use their Psychic Powers.
 * There are several species of Psychneuein, such as those inhabited Prospero - creatures that follow psychic power so they could lay eggs in the psyker's head. Non-psykers aren't exactly safe either, but how much they're acceptable as hosts depends on the specific breed.
 * Magic Knight: Space Marine Librarians, Chaos Sorcerers, Eldar Warlocks, some militant psyker orders training with force weapons... the Grey Knights are a whole army of these.
 * Magic Misfire: Perils of the Warp.
 * Magitek: Mostly the Eldar and the Necrons, though Imperial and Chaos gear crosses into this sometimes.
 * The Magnificent: Kharn the Betrayer, Abaddon the Despoiler, and Scyrak the Slaughterer, among others.
 * Man-Eating Plant: Crop up all the time on Death Worlds.
 * Man in the Machine: Space Marine Dreadnoughts, Ork Deff Dredz and Killa Kanz.
 * Maybe Magic, Maybe Mundane: 40k loves this one, given how blurry the line between magic and technology tends to be.
 * Meaningful Name: Both played straight and inverted where Space Marine Chapters are concerned; a popular joke pokes fun at this.
 * In a stunning display of originality, Corax (Greek for "raven") is the primarch of the Raven Guard.
 * In an even more stunning one, Ferrus Manus (latin for "iron hand") is the primarch of the Iron Hands, and he has actual iron hands.
 * And Magnus was a cyclops and is now a Daemon Prince
 * Isha, the Eldar Goddess of life, health, growth and fertility, who whispers the cures to the diseases that Nurgle tests on her, is the Japanese word for "doctor" or "physician".
 * Hilariously inverted with the Land Raider and Land Speeder. Indeed those names are appropriate for the purposes of the vehicles (The Land Speeder is rather fast and can only glide over land, never achieving true flight, while the Land Raider is one badass tank that will make any serious player crap their pants), they're not named because they're Land vehicles, but because their in-universe discoverer's last name was "Land". So it has two meaningful names in-universe, and one outside. Go figure.
 * Mecha-Mooks: Necrons.
 * Mechanical Horse: Krieg Death Riders and the like on the Imperial side, cyboars for the Orks.
 * Mogul Kamir of Atilla had a mechanical horse made for him by the Adeptus Mechanicus, because he kept riding the flesh-and-blood ones to death.
 * A Mech by Any Other Name: Dreadnoughts, Knights, Wraithlords, Gargants, Titans, Crisis Suits, etc.
 * Medieval Stasis: Most of the races in the 41st millennium have been in a state of technological stagnation for thousands of years. Also literal on many worlds.
 * The Imperium bans any technological advancement (there are approved ways, but those are labyrinthine at best), partly as part of their reverence for old tech in their religion, with beliefs of Status Quo Is God.
 * The Eldar are in a decline, with all their efforts focused on keeping their immortal race alive.
 * The Necrons are a machine race that are basically mindless outside of their Lords, and have been asleep for the past 65 million years.
 * The Orks are too stupid and violent to get any widespread scientific progress or anything else outside of what would get them a louder "boom" or deliver them to the places where fighting goes (but sometimes explodes halfway there). Meks have rather kunnin' power field... but mostly it's creative application of Genetic Memory, which is why their designs are mostly uniform.
 * Averted by the Tyranids and the Tau.
 * Mega City: Hives. In the spires the local rulers live, and toward the bottom it becomes more and more hellish, as the systems recycling pollution and industrial waste are imperfect. The underhive usually is lawless and something eats people regularly, but it's allowed to be like this as a safety valve for pushing all the mutants and malcontents from the places that matter.
 * Mental World: The Warp.
 * Merchandise-Driven: Oddly enough, the majority of the background material and fiction does not fall to this trope, although rules modifications and new army lists are often accused of changing stats only to boost sales of certain models, and both the monthly magazine White Dwarf and the Games Workshop website have gradually become less hobby supplements and more miniatures catalogues.
 * Mercy Kill: The Emperor's Peace.
 * Messianic Archetype: The Emperor.
 * Mighty Glacier: Models wielding Power Fist strike last in close combat, but can punch clean through tank armor and pound enemy infantry into a bloody paste. The Leman Russ battle tank is slower than most vehicles its size, but it's a stable firing platform capable of unleashing twice as much firepower as most other tanks at combat speed.
 * Military Mashup Machine: The Imperium in particular has a recurring love affair with these, and the Tau may be starting to lean this way.
 * The Milky Way Is the Only Way: Mostly justified by the limitations of the various races' FTL. The Tyranids come from outside the Milky Way, but nothing more is known.
 * A Million Is a Statistic: And so is ten billion.
 * Mind Rape: 40k loves this one:
 * The process of turning a psychically sensitive human into an Astropath is basically a Mind Rape, though it has a few physical aspects as well, such as their eyes being completely burned out.
 * Daemonic possession.
 * A lot of psychic powers are basically this, most obviously an Eldar power called "Mind War".
 * The psycho/hypnotherapy Space Marines undergo as part of their conversion from human to Astartes is a limited form of Mind Rape, a sort of mental The Spartan Way.
 * And Grey Knight training takes this even further, involving as it does the "Six Hundred and Sixty-Six Rites of the Emperor", which is longhand for 666 mind rapes.
 * Also worthy of mention are the Exorcists chapter of Space Marines, who have a innate edge against Daemons due to their training involving getting deliberately possessed and then exorcised.
 * The Nightbringer Mind Raped proto-life so horribly that he instilled the fear of death in all living creatures in the galaxy, except the Orks (whom he never met).
 * Slaanesh's birth was an act of mind rape upon the Eldar civilization so intense it spilled over from their collective minds and tore open a hole in reality. That's right, Slaanesh mind raped a galaxy!
 * According to fluff, the Harlequins' masks do this if they are worn by anyone untrained in their use (or at least humans) by causing them to hallucinate and psychically forcing the wearer to assume the role the mask is meant for.
 * Mini-Mecha: The Eldar War Walkers and Imperial Guard Sentinels, as as well as some of the larger Tau battlesuits.
 * Mohs Scale of Sci Fi Hardness: Generally soft. In the fiction, this often depends on the writer (see: lasgun depiction). See Battlefleet Gothic for an example of space combat ranges done right (unless when counting Hot Spaceship on Spaceship Action). For the most part, though, Rule of Cool is physics.
 * Moody Mount: Juggernauts of Khorne.
 * Mook Maker: Some of the Tyranid critters, such as the Tervigon and the Parasite of Mortex, have the ability to spit out smaller creatures.
 * Also, the Necron Tomb Spyder is another noteworthy example, putting out scarab swarms at a small risk to itself
 * Mordor/PollutedWasteland: Most hive worlds and other heavily-industrialized human or ork planets, including Holy Terra.
 * More Dakka: The Trope Namer, and home to the greatest examples in fiction or out of it.
 * More Teeth Than the Osmond Family: Tyranids.
 * More Than Mind Control: Chaos is insidious indeed.
 * Any Tau who can smell an Ethereal will be completely fearless and free of doubt, following any instruction from that Ethereal without hesitation. However, Ethereals cannot always be present. As such, Tau society has been groomed over the generations to follow the will of the Ethereals even when they are not present. A Tau will generally attempt to do what they believe the Ethereals think would be best when separated from one, and to be near one is a source of joy. For the most part, an Ethereal does not need to compel a Tau, as a Tau will be more than happy to obey already. Commander Farsight is a notable exception to this.
 * Mono-Gender Monsters: Orks, all Boyz.
 * Monster Clown: Eldar Harlequins are psychedelic space elf ninja killer clowns. They wear holographic harlequin costumes and extremely scary masks, and carry horrifyingly nasty weapons even by 40k standards; as an example, their usual squad support weapon fires molecule-edged crystal discs covered in toxins that make the target's blood explode. They worship the "Laughing God", and are the Eldar equivalent of a roving carnival, visiting the various Craftworlds and acting out tales from Eldar mythology with holographic, psychically-enhanced interpretive dance. When they're not killing people in unspeakably horrible ways, that is.
 * Just to put this one in perspective, the Dark Eldar, a race of beings who have an almost genetic urge to torture people in anatomically horrific ways, are terrified of the Harlequins and dare not refuse them entry into the normally impregnable dimension they reside in.
 * Moral Myopia: To elaborate on the above, when the Eldar are faced with a choice between safeguarding their own kin and the welfare of another species, they will pick their own kind every time. Which is perfectly understandable - just not much fun when you're the one getting screwed in their stead. And especially after the Eldar have decided that a couple thousand of their lives are worth several million of yours.
 * Morally-Ambiguous Doctorate: Ork Mad Doks and Painboyz to a Boy.
 * Ork medical knowledge is genetic, and anyone claiming to be a dok is licensed to operate. That doesn't necessarily mean you'll like the results, though....
 * Moses in the Bulrushes: The Primarchs, Mortarion especially.
 * Multi-Armed and Dangerous: Warp Spider Exarchs, the mandrake Decapitator, certain Mechanicus adepts, some cyborks, every Tyranid ever.
 * Mushroom Samba: Imperial hallucinogen grenades can invoke all manner of humorous and potentially self-destructive delusions in their victims.
 * Musical Assassin: Noise Marines and Goff Rokkerz kill with The Power of Rock.
 * The Musketeer: Imperial military training teaches proficiency in both melee and ranged combat; most Imperial troops, Guard and Marine alike, are equally skilled with gun and blade, even when equipped for a more specialized melee or ranged combat role.
 * In the tabletop game, however, it's pretty clear the average Imperial Guardsmen just have no chance in hell against anyone else in close-combat aside from other humans or the Tau.
 * Mutant Draft Board: The Adeptus Astra Telepathica, responsible for human psykers.
 * My Country, Right or Wrong: The Imperial Guard sometimes gets this treatment, especially when they're the antagonists.
 * My Significance Sense Is Tingling: Psykers can sometimes feel the psychic backlash of mass deaths or other strange events in the Warp. They can also detect the warp shadow of an oncoming Tyranid hive fleet... often by going insane and dying.
 * Mystical Plague: Nurgle mages get these kinds of spells.

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 * Names to Run Away From Really Fast: Chaos leaders' names like Kharn, Abaddon and Scyrak sound scary enough, and then you find that their respective nicknames are "the Betrayer", "the Despoiler" and "the Slaughterer". Ork names tend to be made up of words like "smash" and "skull," and that's before you get to the self-given titles like "Arch-Arsonist," "Arch-Dictator," "Arch-Maniac," and for a change of pace, "Da Big Bad Beast."
 * Abaddon literally means "the destroyer".It also means "the Devil" and "Hell".
 * Also names like Decapitator or the Red Terror.
 * Dark Eldar get in on this, too. Lelith Hesperax, Urien Rakarth, and Asdrubael Vect, Supreme Lord of the Kabal of the Black Heart are all about as nice as they sound.
 * Nanomachines: It's not quite clear whether Necron "living metal" is made of 'em, but there are several application even within the Imperium.
 * Autosanguinator implants (traditional) have blood filled with injury-repairing machines. Hermetic Infusion (restricted to tech-priests) is a more powerful version, which replaces blood - as such, it makes transfusions and many other treatments designed for humans... inapplicable, though a Magos Biologis can help - not that it's needed often, with major Healing Factor and resistance to material contamination this gives.
 * Core Gel (widely used where it's needed, but still contested by some tech-priests) temporarily provides universal interface via application to skin.
 * Bioforging (unequivocally heretical, since it causes genetic damage for some reason) grows subdermal armour, increases general toughness and allows to briefly survive in vacuum, but causes dependency on eating exotic fuel and without tricky maintenance plastic starts growing in all the wrong places, which quickly disfigures and kills the "beneficiary".
 * Necessarily Evil: Imperial servants in general, and Inquisitors in particular, knowingly and willingly do horrible things to innocent people on a regular basis because the consequences for not doing so could be catastrophic for humanity as a whole.
 * Neglectful Precursors: Strangely enough, inverted as it's more like neglectful moderners. Back in the golden age of technology, people were smart enough to create standard template constructs (STCs) allowing any colony to build whichever it may need from the ground up (amount of the required efforts may vary). Anyone who had one could build anything from a house to a tank if the situation required, regardless of ability or technology. Ten thousand years later, these same items created millennia ago are still in use, but the massive galaxy-spanning Imperium appears to be having trouble finding the things.
 * To be more exact, the Imperium is having trouble finding even drawings of the things. A single ancient sketch of a blueprint taken off a broken STC (broken is as good as they come after 20,000 years or so) is a prize enough to burn entire star systems. Or gift said systems to the blueprints' finders.
 * New Technology Is Evil: A cornerstone of the Adeptus Mechanicus.
 * Ask any two Magi and you'll get at least two answers, though. It ranges from They all believe in the existing rituals of construction and maintenance, most believe in reverse engineering, enough believe in "respectful improvement" that new weapons do emerge, and they sometimes fight each other over whether xenos tech can be studied and recreated in a "purified" form or is just a blasphemy against the Machine-God.
 * Nice Hat: Commissars', though the wearers aren't.
 * Nietzsche Wannabe: And they're the unbelievably and naively optimistic in this setting. Be honest and ask yourself what's worse: a cold and uncaring universe, or a universe actively out to get you?
 * Nightmarish Factory: Mars and forge worlds in general.
 * Night of the Living Mooks: Necrons.
 * Night Vision Goggles: Tau blacksun filters, Imperial "heat see" preysense devices and Space Marine autosensors.
 * Ninja Pirate Zombie Robot: *deep breath*:
 * Repentant fanatical bondage nuns with chainsaw flamethrowers.
 * Psychic space elf torture-obsessed ninja bondage pirates/psychedelic ninja killer clowns/knights on flying bikes with laser lances/wizards/split-personality warriors with chainsaw swords and guns that shoot ninja stars/Luddite wood-elf hippie dinosaur riders.
 * Skin-stealing soul-eating green-lightning-spraying undead doom robots.
 * Psychic genetically engineered fanatically religious daemon-killing knights.
 * Genetically engineered green-skinned soccer hooligan axe-crazy techno-barbarian space-orc aliens who are subconsciously psychic.
 * Asian caste-based bunny-eared-mecha-using alien hooved collectivist suicide bombers.
 * Axe-waving blood-drinking/mutated burning tentacley/rotting maggot-ridden cyclopean/androgynous crab-clawed sex-fiend psychic emotion eating daemons.
 * Viking/Mongol/Roman/Spartan/perverted Sense Freak bondage-obsessed/AxeCrazy/magic zombie/cyborg/vampire/Daemon-possessed genetically engineered power-armoured super-soldier warrior monks.
 * No Hugging, No Kissing: Unsurprisingly, the subjects of love and romance tend to be completely glossed over in the setting and all of its spin-offs. As noted on its page, Warhammer 40k prefers to minimize the love story aspect of its approach to Space Opera.
 * It's actually quite justified when one takes a closer look. Space Marines are largely asexual (whether by choice or conditioning is a matter of no small fan debate), the Eldar largely repress sexual desire to avoid falling prey to the urges that brought about the Fall, the Tau view sex simply as a matter of procreation, Orks are Mono-Gender Monsters, the Necrons can no longer procreate, the Tyranids are hatched, and most Chaos followers are too furious, too mutated, or too rotten to care about sex. The only groups which do engage in this aspect are the Imperial Guard, the Slaaneshi, and the Dark Eldar...and you really don't want to know about the last two.
 * Non-Human Undead: Undead Daemons created from the souls of those killed (not NOT turned into the undead) by the undead plague, undead statue robots (wraithguard and wraithlords) Undead Wizard Statue Robots (Wraithseer and Warlock Titans). Undead Robots (necrons) and Undead Mecha (Dreadnoughts to a degree and Nurgle Titans). Surprisingly no Undead Dragons (then again, their fantasy counterpart fills in whatever holes it has).
 * No One Gets Left Behind: Thoroughly averted for the most part - the Tau and Eldar are about the only ones who ever try, and the Eldar consider recovering the waystones of the dead good enough consolation for being unable to save the bodies of the living (because the waystones contain the soul of the dead Eldar). Similarly, although the Marines consider it the highest honour to die in battle, they'll fight hard to recover the progenoid glands from the still-cooling bodies of their battle brothers.
 * Black Templars will risk life and limb to recover the body of a fallen Emperor's Champion.
 * Necrons have an automated version of this.
 * Also, given the Cargo Cult/Ancestral Weapon nature of technology in the Imperium, the Adeptus Mechanicus and the Space Marines will often insist, and go to sometimes-absurd lengths to ensure that No Tech Gets Left Behind.
 * Somewhat played straight by the Emperor's Champion of the Black Templars, where his brothers are willing to sacrifice dozens of other marines to retrieve his body should he fall.
 * Orks invert this trope brutally and repeatedly.
 * It's actually built into their genetics (again! noticing a pattern?) so that when they die, they release a huge bunch of spores to grow into more Orks.
 * No Plans, No Prototype, No Backup: Even the best and brightest Mekboyz don't know how some of the things they build work, or occasionally even what they had in mind when they started nailing bits on. Often the purpose of a Mekboy speshul invention can only be determined by testing it, a dangerous pursuit.
 * Also justified for a lot of Imperial tech, thanks to it being Lost Technology.
 * Nothing but Skulls: Most commonly associated with the Imperium. Yes, the good guys protagonists. They're also known for using cyborgs flying skulls, both utility and Attack Drones.
 * Orks, followers of Khorne, and Dark Eldar aren't slouches in the skull-taking department, either.
 * Not So Different: The Imperium and the Eldar are both avowed enemies of Chaos and both elitist xenophobes. Naturally, each considers being compared to the other to be a dire insult.
 * Inquisitors for most part are people who don't consider themselves bound by the Imperium law and traditions, chasing whatever purpose they perceive as worthy, for most part operating secretly via networks of weakly connected cells. Exactly like most heretics. The irony is acknowledged.
 * Noun Verber: Lots of Space Marines, both Imperial and Chaos: World Eaters, Word Bearers, Soul Drinkers, Flesh Tearers, Flesh Eaters, Blood Drinkers, Skull Takers, Deathmongers, Fire Reavers....
 * Nuke'Em: Standard Imperial policy on dealing with anything more dangerous than an angry dog. Usually the right thing to do. Occasionally not enough.
 * A particularly Egregious example is the Death Korps of Krieg, who "subjected their homeworld to a 500-year campaign of atomic cleansing."
 * Number of the Beast: The Grey Knights are Chapter 666, and their initiation involves the 666 Rites of the Emperor. They hunt daemons.
 * Numbered Homeworld: Both averted and played straight.

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 * Obstructive Bureaucrat: Planets of them. At least one of them is actually on the verge of civil war because they're running out of places to store the paperwork.
 * Obviously Evil: Played straight, but also possibly subverted depending on just how "evil" you consider the Imperium.
 * Obvious Rule Patch: White Dwarf used to give out official rulings against interpreting the second edition rules in stupid ways. For example, your Imperial Assassin using the shape-changing drug Polymorphine is not allowed to disguise himself as a tiny Gretchin while wearing Terminator Armour and riding an armoured motorbike just because the rules don't specifically say he can't.
 * A Commissar (of any rank) will never execute himself.
 * Officer and a Gentleman: The Imperial ideal. True to real life, many are also corrupt, incompetent, treasonous, or all-around bastards.
 * Offscreen Villain Dark Matter: Ten thousand years of continuous war, and the Traitor Marines are still in bolter shells. This has been made somewhat less ridiculous in recent fluff, with mention of Chaos forge worlds, and a change in focus towards Renegade (recently-corrupted) Marines to distract from the question of how the original Traitor Legions even still exist. And since they do reside in the Eye of Terror, where "physics" is even more of a joke than elsewhere, they have literal Offscreen Villain Dark Matter.
 * The Ogre: Ogryns of the Imperial Guard, armed with automatic shotguns designed to be equally useful as giant clubs (they will use any weapons like this, the difference is that Ripper Guns are built to withstand such treatment).
 * Feral World Ogryns, from the abhuman rules in White Dwarf, don't even get the shotguns.
 * Oh Crap: The general logical conclusion from infantry squads taking a leadership test in the tabletop. While some examples are psychic powers messing with them, it's otherwise watching the rest of their squad get killed horribly and/or in quick succession and reasonably figuring that they'll be next.
 * Older Is Better: Thanks to the Imperium's habit of forgetting how to build their own tech. Same goes for the Eldar.
 * Old Shame: GW regards the Squats and Zoats as "things better left forgotten." However, hints of them do pop up in new material from time to time...
 * Ominous Latin Chanting: Well, Ominous High Gothic Chanting, really.
 * Omnicidal Maniac: Tyranids, and certain Chaos factions to some extent. Orks too, just for fun.
 * Necrons were this until the most recent codex, where their main motivation is not killing everyone but ruling everyone. They'll still gladly kill whoever treatens their empires, though.
 * No, their motivation was changed from wanting to kill all life out of hatred, to wanting to exterminate all other life so that they can regain their former empire. To quote the codex, "They seek to destroy the lesser forms of life that infest their old domains, and re-establish their rightful rule."
 * One-Gender Race: Justified by the Orks because they reproduce asexually and are biologically a lot like fungi. Justified by Space Marines for genetic engineering reasons and Sisters of Battle for political loophole reasons. Avoided by Eldar, Dark Eldar and Imperial Guard. Mostly played straight by the Tau. Don't even ask about the Necrons or Tyranids.
 * Tau have different sexual characteristics from humans. The female dissected in Xenology is nearly indistingushable from a male Tau. End result: you could be fielding an all-female or all-male or mixed group of Fire Warriors. There's no way to know.
 * The Tau do not seem to have much trouble determining which other Tau are male or female so this may also be a case of You All Look Familiar. The distinction beteen male and female Tau is more subtle than that of humans.
 * One-Man Army: The entire point of Space Marines. Also taken to ridiculous limits by Shas'la Kais from the forgettable 40k FPS Fire Warrior. Also the Primarchs and the members of the Adeptus Custodes.
 * One World Order: The Tau Empire, though as their fluff is expanded, differences between Tau Septs are starting to appear.
 * Only Sane Man: Possibly the Tau Empire, though this is more of a subversion - it's the insane people who are completely correct and realistic about things, and the sane Tau seek to play by the rules in a universe that has none.
 * Arguably, the Emperor of Mankind was this for the Imperium. And now he's locked on life-support, unable to do anything as his race and Imperium go straight to Hell.
 * Order Versus Chaos: Generally accepted as Imperium, Eldar, and Tau for Order, and Orks, Dark Eldar and, well, Chaos for Chaos. Necrons and Tyranids are off to the side a bit.
 * One could argue that the Necrons are also on the side of Order - just that their method of defeating Chaos (the ideology, not the faction) is to kill off anything and everything else that could possibly upset the natural order of the universe, i.e. sentient life.
 * Organic Technology: See Tyranids again.
 * Original Position Fallacy: Many people who join Chaos cults do so in the hopes of attracting their chosen god's favor. Unfortunately for them, said gods are just as likely to ignore them, give them what they want or subject them to horrible (or benign) mutations.
 * Our Monsters Are Different
 * Our Angels Are Different: Do your (Blood) angels wield automatic rocket launchers and chainsaw swords? We didn't think so.
 * Our Demons Are Different: A daemon is technically any being that dwells in the Warp, but true daemons in 40k are the personifications of rage, despair, pleasure, or hope - and not even those last two are pleasant.
 * Our Dragons Are Different: Dragons are creatures of Eldar myth, but it's recently been indicated that the C'Tan Void Dragon takes a dragon-like avatar as well.
 * Our Dwarves Got Eaten By Giant Bugs And We Don't Talk About Them Anymore. Got It?
 * ...But Our Other Dwarves Are Still All The Same: The Demiurg, from what little we've seen of them, are still stocky, Ork-hating, hairy miners and traders... IN SPACE!
 * Our Elves Are Better: Two main subspecies, the Eldar and the Dark Eldar. Both are pointy-eared clairvoyant bastards; the Eldar place more emphasis on the "clairvoyant" part of the description, while the Dark Eldar put more emphasis on the "bastards."
 * Our Gargoyles Rock: Rather than the standard magical stone statue, Gargoyles are Tyranid air units that cling on to a bigger flier for long-distance flights.
 * Our Ghosts Are Different: ...and armed to the teeth. See Necrons, especially Wraiths.
 * Our Giants Are Bigger: Big Mutants, larger subtypes of Ogryn.
 * Our Goblins Are Wickeder: Gretchen/grots serve the Orks as ammo runts, ammo, emergency rations, las-shields, bullet shields, better footing, minefield clearance, rocket guiding systems and spare parts, among other things.
 * Our Gods Are Greater: The Chaos Gods, the C'Tan and the Ork gods of cunning brutality and brutal cunning.
 * Our Ogres Are Hungrier: Ogryns, humans mutated to be extremely tough and strong, but with drastically reduced intelligence. Wield shotguns specifically designed to be used as clubs.
 * Our Orcs Are Different: Traditional fantasy Orcs meet football hooligan stereotypes meet a whole lot of dakka and Mad Max/Reaver type vehicles/ships. It says a lot about just how horrible the 40K universe is that these crazed, violent lunatics, whose societies revolve around killing or brutalising anyone and everyone - including each other - are the comic relief race.
 * Our Souls Are Different: The Warp, mostly.
 * Our Vampires Are Different: Are your vampires made by being genetically modified from a practical angel's genes?
 * 1st edition 40K Rogue Trader also had actual creatures called Vampires, which were polymorphic giant humanoid bat-things which originate in the Warp and can mimic any other vaguely human-sized organism.
 * Our Werewolves Are Different: Wulfen, failed/corrupted Space Wolves.
 * Our Weapons Will Be Boxy in the Future: And if you're the Imperium or the Orks, so will your vehicles and buildings. Tau also have boxy weapons, though their vehicles and their architecture tend towards more rounded and organic-looking shapes.
 * Outgrown Such Silly Superstitions: The Imperium was created as a galaxy-wide example of this trope, and during the course of the Heresy became a comprehensive and horrible subversion.
 * Of course, there is a school of thought that says the Emperor only tried to steer humanity away from religion precisely because he KNEW there were gods out there, and nasty ones at that. Then there's some subtle references in at least some of the novels that suggest the Emperor to be the fifth sixth  seventh latest Warp God, who is only prevented from kicking the snot out of the other big four because he is still tethered to his mortal form...
 * Out of the Inferno: Happens a lot, especially with Space Marines, Orks, and particularly Necrons.
 * Outscare the Enemy: Part of the Commissar's job is to embody this. Probable death at the hands of of reality-defying abominations or a Horde of Alien Locusts may be terrifying, but certain death for "cowardice" is a big motivator.
 * Outside Context Villain- The Tyranids were this to the Ultramarines because the latter's Big Book of War had no combat plans against that kind of enemy, leaving them tactically flat footed.
 * Overshadowed by Awesome: Various examples, with the Imperial Guard probably being the clearest example.

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 * The Paladin: Brutally deconstructed with the Gray Knights, played fairly straight with the Salamanders..
 * Parental Issues: The Emperor and the Primarchs.
 * Truly Single Parent: The Emperor was responsible for the creation of the twenty Primarchs before the start of the Great Crusade, at least partly from his own DNA.
 * Parental Abandonment: The infant Primarchs were scattered through the Warp by the Chaos gods, coming to rest on various human worlds throughout the galaxy. It was, to be fair, hardly intentional, but they were all adults before the Emperor found them again.
 * Like Father, Like Son: Of the eighteen known, each Primarch had risen to a position of power before they were found, and most were the rulers of one or more planets.
 * Raised by Wolves: Literally in the case of Leman Russ, more figuratively for some of the others.
 * Parental Favoritism / The Unfavourite: Horus was the Emperor's "first son", both in order found and as the Warmaster of the Great Crusade, while some of the Emperor's decisions about his other children (especially concerning Magnus the Red) have been... questionable.
 * Calling the Old Man Out: The Horus Heresy. Never let it be said that 40K does things on a small scale.
 * Offing the Offspring: As a direct result of the above.
 * Cain and Abel: Guilliman killed Alpharius after Horus' followers scattered, and was later mortally wounded and forced into stasis by Fulgrim.)
 * In all likelihood,.
 * Horus killing Sanguinius for refusing to join him before the final fight with the Emperor.
 * Promotion to Parent: Roboute Guilliman essentially promoted himself after the Emperor's death/ascension/interment.
 * Rage Against the Mentor: Alpharius, against Roboute Guilliman, although Alpharius admitted nothing more than a pragmatic indifferance to his brother's boasting. Other examples include Rogal Dorn, Primarch of the Imperial Fists, masters of fortification and endurance and Peturabo, the Primarch of the siege expert Iron Warriors.
 * Perhaps the biggest example of this trope is that of Horus and Abaddon. Abaddon looked up to Horus, and his loyalty (before and during the Heresy) was greater than any other...except for when Horus eventually loses the siege of Terra and Abaddon starts having second thoughts. Cue taking immediate command of all chaos forces and retreating back to the Eye of Terror, thus coining the phrase "Horus was weak, Horus was a fool". Such was his hatred of Horus's weakness, Abaddon renamed the Sons of Horus legion to the Black Legion and, upon hearing about even the potential to clone Horus, launched an all out attack to destroy the project. Not that Abaddon has done much better than Horus... 13 Black crusades later and not an awful lot has changed...
 * People Jars: How you get a new Space Marine Chapter, amongst other things.
 * People Puppets: Occasionally seen as an ability of psykers.
 * Percussive Maintenance: One battle report jokes about a Techmarine fixing a complete tank engine with "a lot of chanting, and a few hammer blows." The startup procedure for hololiths and cogitators throughout the Imperium also includes a "ritual blow to the side of the casing."
 * According to supplementary materials, this is actually an official Adeptus Mechanicus repair procedure: "The Ritual of the Knock."
 * Ork Meks as well, owing to the simple and robust nature of Ork technology (and possibly Clap Your Hands If You Believe).
 * Perplexing Plurals: Good luck getting the fans to agree on a plural for "Carnifex".
 * Person of Mass Destruction: Untrained Psykers are regarded as these by the Imperium, with good reason.
 * Phantasy Spelling: Chaos "daemons" might or might not be an example of this. The word technically means "minor deity", but since that's what a lot of daemons actually are...
 * Phantom Zone: The Warp.
 * Physical God: The Emperor may have been one of these, and the Primarchs were basically demigods; also, the Avatars of Khaine and the C'tan. Daemon Princes can sometimes have pretty god-like powers, too.
 * Pirate: IN SPACE!
 * Pistol-Whipping: A game mechanic.
 * Planet Eater: The Tyranids are this, and intend to do it to every life-bearing planet in the galaxy.
 * Planet of Hats: Applies to several races, to try and reduce their Separate but Identical nature.
 * Imperial Guard: Everyone from Cadia is a soldier, everyone from Krieg is an exceptionally grim and dour soldier in a longcoat, everyone from Praetoria is a Zulu extra, everyone from Catachan is Rambo (but more hardcore)...
 * Eldar: Five major subfactions are each a Craftworld of Pointy Helmets: everyone from Ulthwe is either a professional soldier or a Seer, everyone from Alaitoc is a hooded loner with a sniper rifle, everyone from Biel-Tan is an Aspect Warrior, everyone from Saim-Hann rides a flying bike, everyone from Iyanden is dead.
 * Orks: Every Goff is grim and dour and takes fighting (comparatively) seriously, every Evil Sun is fanatically obsessed with fast-moving red vehicles, every Deathskull is a thieving bastard who welds guns together into bigger guns, every Bad Moon is a rich bastard who buys all the best wargear, every Snakebite is a backwoods hick who clings to traditional ways of doing things, and every Blood Axe is a sneaky bastard who believes in un-Orky things like tactics and camouflage.
 * Space Marines: Ultramarines are all Romans, Space Wolves are all Vikings, White Scars are all Mongols, Black Templars are all, actually, Teutonic Knights (Germanic names, not to mention the colour scheme). Dark Angels were, at one point in their history, all Native Americans, which is why the Deathwing Terminators have feathers and beads hanging from their armour.
 * All Blood Angels and descendants become bloodthirsty cannibals, all Iron Hands are anti-emotional cyborgs, all Imperial Fists are siege engineers and all Grey Knights are Paladins (though they're distinct from the other chapters).
 * Chaos Space Marines: Every Word Bearer is a religious fanatic, every World Eater is a berserker, every Thousand Son is an Egyptian style sorcerer or an empty shell, every Death Guard is a rotting bloated disease bag, all Emperor's Children are hedonistic heavy metal guitarists (except Fabius Bile), every Iron Warrior is a siege engineer, every Night Lord is a scary ass serial killer, and every Alpha Legion is a sneaky, identical, unorthodox Chessmaster.
 * Before they became Slaaneshi, the Emperor's Children were all perfectionists. Former Chief Apothecary Fabius Bile still is.
 * Planet Looters: Mostly Orks, but occasionally the Imperium. Tyranids and Necrons go some way beyond "looters".
 * Note Orks will occasionally loot a planet and turn it into a spaceship of ridiculous size.
 * Well they don't use the planets themselves, but they equip large asteroids with a planet worth of weapons and some engines (big ones), and then go merry hunting around the galaxy in their new "Da Rok".
 * Planet Terra
 * Planetville: Averted and played straight in equal measure. A lot of fluff has, often for game reasons, the fate of systems decided by tiny battles, while just as much - particularly the novels and worldwide campaigns - features thoroughly "realistic" planetary campaigns, with millions upon millions of soldiers and years of fighting involved.
 * Plant Aliens: The Orks are symbiotic creatures, a seemingly mammal-like anatomy with a fungus in its skin and blood, meaning they have green skin but red blood. They reproduce asexually, giving off spores all the time which grow new Orks in underground wombs, and as a result are nearly impossible to completely wipe out by any means short of planet-wide firey holocaust.
 * Pleasure Planet: Garden Worlds.
 * Plot Armor: All races to an extent but some tend to have more than others. The most extreme example of this trope are the Tau, which earns them a certain degree of hate from the fan base.
 * Plucky Comic Relief: You know you're on the extreme end on the cynical side of the scale when this role is filled by the rampaging, murderous hordes of Orks, whose idea of a good time is to indiscriminately kill anything, including each other, and introducing people's internal organs to daylight.
 * The Political Officer: Commissars. The Severan Dominate's secession had them removed... and replaced with Ducal Legates.
 * Politically Incorrect Hero: Subversion in that the Imperium is only considered heroic in comparison to the other factions in the galaxy.
 * Politically-Incorrect Villain: Considering the trope listed above, it's more like Politically Incorrect Everyone.
 * Portal Network: The Eldar Webway.
 * Power Born of Madness: Followers of Chaos are generally crazy enough to do anything, but the Imperium itself acknowledges this trope: "In the darkness, a blind man is the best guide; in an age of madness, look to the madman to lead the way."
 * Power Crystal: Eldar have their "Waystones", a gem worn over the heart which captures the soul of the Eldar upon death to prevent it from being painfully devoured by the Chaos god Slaanesh. These spirit stones allow the Eldar a peculiar kind of necromancy with Wraithguard and Wraithlords, battle constructs controlled by the spirit of a long-dead Eldar in a waystone. The Eldar also pimp out their vehicles and weapons with countless more mundane gems.
 * Power Fist: Trope Namer.
 * Power Floats: C'tan.
 * Also the Zoanthrope. How else could such an atrophied body support that enormous head?
 * Power Gives You Wings: Living Saints, daemon princes.
 * Power Incontinence: Usually human and Ork psykers, but also some Chaos sorcerers.
 * Power Limiter: Applied to psykers such as Astropaths and Guard Sanctioned Psykers, making them less powerful but a little less likely to go insane and melt everyone.
 * The Power of Rock: Slaaneshi Noise Marines. Corrupt power armoured super soldiers armed with daemonic killer guitars, who blow people apart with their power chords.
 * Ork Goff Rokkerz also fit in here.
 * Power Perversion Potential: In the Dark Heresy RPG, if you fail to summon a daemon properly, it will materialize in a puny size. All of /tg/'s Lolicon Warhammer fanatics rejoice, as they can finally have their Loli daemonette.
 * Slaanesh is literally the god of Power Perversion Potential. If you're a servant of Slaanesh who doesn't use the god's Gifts in this way, you're doing it wrong.
 * Power Armour: Ubiquitous.
 * Imperial: Varies from what-it-says-on-the-tin man-sized suits of armour that can carry themselves and protect against conventional small arms, to the ridiculous terminator armour (or tactical dreadnought armour) that's a hybrid of "conventional" Power Armour with Hazmat Suits built to work in plasma reactor cores and EVA on orbits under micrometeoritic bombardment, typically comes with an integral Power Fist and can let the user one-hand most heavy weapons, to dreadnoughts, walking tanks that use space marines preserved in integral sarcophagi after near-fatal injuries.
 * Chaos: As above, corrupted by the forces of spiky Chaos and pulsating with daemonic energies, screaming faces and trophy racks of skulls . Also, might involve horns and tentacles.
 * Eldar: Advanced body-suits made out of living plastic covered in gems, can change shape according to the will of the user and frequently come with psychically activated helmet-mounted nasties. Generally doesn't enhance strength but can come with integrated weapons. Can also come equipped with holographic generators, which let them dance around while the enemy think they're somewhere else, which while being utter genius, is useless against someone blasting you with a tank (In theory).
 * Dark Eldar: As above with blades and Spikes of Villainy... when they bother to wear it.
 * Orks: The Scrapheap Challenge approach to power armour: gigantic ramshackle suits bolted together out of giant pistons and tank parts with ridiculously big cannons and huge bladed claws all over, powered by anything from nuclear reactors to steam, lumbering and lethal for the user but practically unstoppable.
 * Tau: Animesque suits ranging from Tau-sized bodysuits with cloaking fields to mini-Humongous Mecha mounting vehicle-killing railguns and packing small saucer-shaped drones for shielding. Usually lacks competent melee weaponry, though. Granted, the suit itself is strong enough to make a tank explode by kicking the engine, but that doesn't change the fact that the Tau inside fights like a little old lady.
 * Praetorian Guard: The Adeptus Custodes.
 * Also note that the Imperial Guard regiment called the Praetorian Guard has little to do with the trope.
 * Pre-Ass-Kicking One-Liner
 * Prescience Is Predictable
 * Pretty Little Tank Piercing Shots: The description of Tau railguns in the Tau codex says that there was a little entry hole in the front of a Leman Russ, a little exit hole in the back, and the liquified remains of the crew forming a 20ft stain coming out the back of the tank. Gibs do not get much more ludicrous.
 * They based that description on real life, as that is what actually happens to the crew of an armored vehicle when it is hit by a modern AP round. Sometimes IRL is Rule of Cool too.
 * Primal Fear: Apart from being made largely out of hideous monsters and darkness, Sarpedon's main psychic power in the Soul Drinker series deserves points: it's called the Hell, and it conjures illusions of whatever Sarpedon thinks will scare the crap out of the enemy, such as making all his Marines three times as large or causing hellbats to come out of nowhere.
 * The C'tan Nightbringer, who has the honor of being the origin for the fear of death in all living things (as well as the Grim Reaper figure) - except the Orks and Tyranids, of course.
 * Primordial Chaos: The Warp.
 * Private Military Contractors: For all the Tau's efforts at securing their loyalty, the Kroot will work for anyone who can offer appropriate compensation. Ork and Dark Eldar mercenaries have also been seen on occasion, as well as Human ones.
 * Properly Paranoid: Justified - if you're not paranoid in this setting, you should be: everything really is out to get you.
 * Prophetic Names: A note to anyone founding a Space Marine Legion: if they call themselves something like the Night Lords, Death Guard or World Eaters, you may want to keep an eye on them. Especially if any of the top officers have names like Night Haunter or Abaddon. This tendency led to the creation of the name "Brother Chaoslover Belial O'Satan" on the Inquisitor fora. No prizes for guessing where his alliegance lies.
 * Subverted by the Emperor's Children. There are also loyalists named Dark or Blood Angels (though a faction of Dark Angels did turn their backs on Daddy).
 * Flat out subverted across the board if you look beyond the Legions, with names like the Angels of Damnation, Marauders, Rampagers, Destroyers, Soul Drinkers, Flesh Tearers and Mortifactors. All belong to well known Loyalist chapters, although the Flesh Tearers subvert the subversion by behaving in a way Kharn would be proud of.
 * Similarly, naming your planet Tartarus or Armageddon is just asking for trouble.
 * Proud Warrior Race Guy: Khorne Berserkers are one part this to nine parts Axe Crazy. And "Orks iz made for fightin'." Space Marines also qualify to some extent. Also: Biel-tan, Lucius the Eternal, Cadia, the Tau Fire Caste . . . let's just say 40k is quite fond of this trope and move on.
 * Psychic Link: Eldar specialise in these. Humans sometimes bind a psyker with someone else, usually bodyguard (in rare cases when a psyker is considered valuable).
 * Also, soul-binding, performed both by Chaos cultists (to their gods) and Astropaths (to the Emperor).
 * Psychic Powers: In the background, necessary for FTL travel, but carry the risk of being possessed or worse by daemons. In the game, originally the excuse for a Recycled in Space magic system, now mostly minor but useful powers in some armies.
 * Psychic Static: The Shadow in the Warp.
 * Psycho for Hire: Lots of people, especially the Dark Eldar.
 * Psychopathic Manchild: Orks, to a Boy.
 * Punctuation Shaker: Tau personal names are bad; Tau spaceship names are nigh-unpronouncable.
 * Puny Earthlings: Humans are among the most feeble things that can be seen on the battlefields of the 41st Millenium. The Imperial Guard attempt to compensate for this with weight of fire, very large tanks and sheer numbers.
 * Geneboosted implanted humans however are a completely different matter even before you add the enormous power armour.
 * To be fair, most Imperial Guard regiments have extensively trained in close-quarter combat and are quite skilled for their size, which is why it's possible (if sometimes unlikely) that a bayonet-fixed Guardsman can take down a huge Ork or a nimble Eldar in a fight. Heck, going up against the Tau (canonically averaging about a foot shorter than humans outside of battlesuits and focusing on ranged weapons) is about the one time the Guard gets to pull a banzai-charge with a fairly good chance of victory. Of course, that's why the Tau hire the Kroot...
 * Put on a Bus: Many of the loyalist Primarchs.
 * Putting on the Reich: The uniform of many Imperial regiments, and Commissars in particular.