* ActorAllusion:
** "[[http://www.youtube.com/watch?feature=player_embedded&v=zuzaxlddWbk The Vet and the N00b]]" trailer is both this and a CallBack. Sam Worthington plays the "Vet," after previously appearing as the commando Alex Mason in ''VideoGame/CallOfDutyBlackOps.'' The commercial also calls back to the ''Black Ops'' advertising twice. First, with the tagline "There's a soldier in all of us." Second, having NBA star Dwight Howard appear toting an M16 with a grenade launcher. NBA star Kobe Bryant appeared with the same gun in ads for ''Black Ops''.
** Master Sgt. Sandman of ''[=MW3=]'' was voiced by Creator/WilliamFichtner, who also played a Delta operator in ''Film/BlackHawkDown''.
* BannedInChina: ''Modern Warfare 2'' was banned in Russia for a while, though the game is now available (apparently with some cut content), including from Russia's biggest online retailer, Ozon.ru.
* BeamMeUpScotty:
** The famous line "Fifty thousand people used to live here... now it's a ghost town." was not spoken by [=MacMillan=]. It was actually spoken by Gaz in the intro. [=MacMillan's=] line in the game is "Fifty thousand people used to live in this city. Now it's a ghost town... I've never seen anything like it." Oddly, [=MacMillan=] ''does'' say that line in the Wii port.
** There's a form of this in-series: part of Zakhaev's speech from "Ultimatum" in ''1'' is reproduced in the introduction for ''2'' - "My son's blood, on their hands." The original speech didn't include the word "son".
* CashCowFranchise: In spades. ''2'' had the largest first-day gross in entertainment history. Not just video games -- ''all'' of entertainment, including movies and music... that was then beaten by ''VideoGame/CallOfDutyBlackOps''... that was also beaten by ''Modern Warfare 3'', which managed to smash [=MW2=]'s record by over a hundred million dollars. Say what you like about the quality of the games, they certainly can sell them. The developers certainly said they would want to continuously make more games even after Modern Warfare 3 in a live interview. [[VideoGame/CallOfDutyGhosts And they certainly did.]]
* CowboyBebopAtHisComputer:
** Zakhaev is often stated to have a [[BlingBlingBang gold-plated]] [[HandCannon Desert Eagle]]. The golden weapons are all multiplayer-only, but apparently some people conflate the existence of the golden Deagle (being the only one unlocked just by ranking up, rather than accomplishing every challenge for every weapon in a class) with the fact that Zakhaev is the only named character in the campaign to make use of a Deagle; that or they assume "bright and shiny", which the regular Deagle in-game is, to automatically mean "gold-plated".
** A lot of people also seem to believe that the smallest weapon on the AC-130 used in "Death from Above" is a pair of 20mm Vulcan cannons. Nevermind that if they'd actually paid attention when playing the game, they would see that the information in the loading screen says it's a ''single'' 25mm cannon [[note]]although the wireframe model of the plane [[JustPlaneWrong does show two cannons, but that's another can of worms]][[/note]], and in the actual gameplay there is only the one cannon, which is explicitly labeled on the HUD and referred to in dialogue as the 25mm Equalizer.
* DevelopmentGag: During [[JustifiedTutorial "F.N.G."]] in ''Call of Duty 4'', if you retry the CQB test and start doing worse at it, [[DrillSergeantNasty Captain Price]] may lament that "perhaps it was a mistake to let you skip the obstacle course." This a reference to a large part of "F.N.G.", including an elaborate obstacle course, being DummiedOut. {{Game Mod}}s have restored the full experience on the PC version (as the audio and scripting necessary were left in the game files and simply needed to be implemented).
* ExecutiveMeddling:
** When the first game turned into a hit in defiance of Activision's expectations, they demanded that Infinity Ward start on a sequel ''immediately'', when Infinity Ward did not initially plan to follow up the series at all. Rumors were abound at the time that Infinity Ward was interested in making a sci-fi game instead.
** Activision CEO Bobby Kotick broke up the Infinity Ward development team after development of the second game due to drama over royalty payments, and gave co-development of ''[=MW3=]'' to series newcomer Sledgehammer Games. Many of the former IW staff members would take the aforementioned sci-fi concept with them, as the next game they would make was ''VideoGame/TitanFall''.
* FakeAmerican: Cpl. Dunn and Sgt. Truck are voiced by the Canadian Barry Pepper and the British Creator/IdrisElba, respectively.
* FanNickname:
** "Grenade of Grenade: Grenade Grenade" and "Stay Frosty [[MilitaryAlphabet Oscar Mike]]: [[DoAnythingSoldier Ramirez]] Do Everything!"
** "Dead Man's Dick" for the Dead Man's Hand death streak in ''[=MW3=]'', courtesy of [=YouTuber=] [=TheShwantz27=].
* FollowTheLeader:
** Changed the gaming world's idea of a "generic shooter setting" from World War II to the modern day with the release of Call of Duty 4.
** The game's multiplayer mechanics, like the deep progression system, customizable loadouts and perks have been frequently imitated by other shooters, to the point that it's considered unusual for a shooter to ''not'' have these features.
* GenreKiller: For WWII games, despite not actually being one. It inspired a wave of similar modern series or modern updates of formerly WWII series like ''VideoGame/MedalOfHonor''.
* IKnewIt: Theories that [[spoiler:[[BigBad Vladimir Makarov]] was the First Horseman]] were correct.
* ItWillNeverCatchOn: Infinity Ward wanted to take Call of Duty into the modern day as early as the second game in the series, but Activision was strongly against it and insisted the series stay in World War II. Even during development of Modern Warfare, Activision was quick to remind Infinity Ward that it didn't expect the game to succeed.
* MeaningfulReleaseDate: November 10th, 2009 for ''Modern Warfare 2'', which was advertised in the trailers as "11-10-09", with the numbers blinking on in sequence like the countdown before an explosion.
* NamesTheSame:
** One of the randomly-generated names for the FSO agents in the ''[=MW3=]'' level "Turbulence" is, minus a single I, the exact same as that of ''World at War''[='=]s Russian PlayerCharacter.
** There's a Pvt. Allen in "The Bog" in Modern Warfare 1. Pelayo, the name of the Super Cobra pilot from the last [=MW1=] Marine mission, can likewise end up attached to random Rangers in [=MW2=].
** Gaz is not to be confused with [[WesternAnimation/InvaderZim Dib's perpetually angry pizza-loving world-hating younger sister.]]
* PropRecycling:
** Closer looks can reveal where Infinity Ward re-used various models to fill out levels. Of note are crashed [[http://en.wikipedia.org/wiki/Technical_(fighting_vehicle) technicals]] in Washington D.C. (oh, those crazy Virginia rednecks), and American police cars on the tarmac at the Russian airport.
** Hidden in plain sight during ''Modern Warfare 3''[='=]s campaign: There's a warehouse that you fight through which is a literal shot-for-shot recycle of a warehouse from [=CoD4's=] multiplayer; even the crates are the same. Various weapons also reuse their ''[=MW2=]'' models in the campaign - most noticeably, the new USP model for the game never shows up outside of Spec Ops and multiplayer, despite a decent chunk of missions giving you one to start with.
* TechnologyMarchesOn: One of the main complaints over ''[=MW2=]''[='=]s inclusion of the TAR-21 among gun circles was that the real gun did not come with unpowered ironsights. This has since changed.
* TheOtherDarrin: Nikolai, [=MacMillan=], Kamarov, and Overlord all get new voice actors for 3.
* PreOrderBonus:
** ''Modern Warfare 2'' has two special versions, the Hardened Edition and Prestige. Hardened contains an art book, steel case and other bonus content, while the Prestige edition contains an IW-branded [=EyeClops=] Night Vision toy. Note that the word "toy" is not a baseless insult - the manufacturer really does advertise it as being for children. To be fair, real night vision goggles would simply cost too much to include with the game. That being said they ''do'' work as advertised: they're effective up to 30 feet or so.
** ''Modern Warfare 3'' had just the Hardened Edition, which came with bonuses such as a free 1-year-subscription to Call of Duty ELITE, a [[GiantMook Juggernaut]]-themed outfit for your Xbox LIVE Avatar, and "Soap's Journal", a document written from Soap's point-of-view, detailing the events of every mission he was involved in across the series. Additionally, preordering the PC version from Steam also gave the buyer a free copy of ''Call of Duty 4''.
* TheRedStapler: Many manufacturers of airsoft replicas have become absolutely drained because of these games. KWA, a former specialist in gas-powered pistols, has stated that their entire stock of Beretta 93R pistols flew out the door in record time, with the reason "thanks to [=MW2=], these things go quick like hotcakes."
* RelationshipVoiceActor: [[Creator/KeithDavid Sgt. Foley]] and [[Creator/LanceHenriksen General Shepherd]] are [[Franchise/MassEffect Admirals David Anderson and Steven Hackett.]] They're even from the same series as a protagonist with the same name as ''Modern Warfare 2''[='s=] antagonist, albeit spelt differently ("Shepard" against "Shepherd".)
* StarMakingRole: Unless he's still remembered for his roles in ''Film/{{Cliffhanger}}'' and ''Series/PrimeSuspect'' earlier before the games, Craig Fairbrass really found recognition for himself through his voice-acting talents in this trilogy, however Fairbrass' fandom and fame really peaked when he dons the mask of Ghost in ''Modern Warfare 2''. It also helped Fairbrass' previous gig, the aforementioned ''Cliffhanger'', to find a new recent gaggle of fans (due to ''Modern Warfare 2'' referencing the film through a name of level and Fairbrass' presence in both projects) with the same can be said for Fairbrass' film debut ''For Queen and Country'' and ''Prime Suspect'' as well as any other project featuring the actor for any gamer who is curious of badass Brit Fairbrass' resume outside and before his COD roles.
* TroubledProduction: The long-brewing conflict between Activision and lead elements of Infinity Ward finally came to a head during the development of ''Modern Warfare 3''. A large portion of Infinity Ward's staff ended up leaving or being forced out, forcing Activision to bring in Sledgehammer Games to finish development of the title. Famously, one of the disgruntled employees leaked the complete plot of the single player campaign almost a year before release, which was widely published by the gaming press. And even before this, much of Infinity Ward's senior staff left after ''2'''s completion.
* UrbanLegendOfZelda: "Sniper Frog" is a running meme within the [=MW2=] community, after an unsourced Website/GameFAQs post claimed that spfg.exe was a program running in the background which essentially doled out luck to players who weren't doing well and handicapped those who were.
* WhatCouldHaveBeen:
** ''Modern Warfare'' had an unusually large number of changes to its single-player campaign, possibly thanks in part to it having been in development in some form for a still-unprecedented-in-the-series four years:
*** The British campaign's training mission was originally longer, calling back to the very first game's training mission with an obstacle course and an area dedicated to using C4, which can be restored via [=PC=] modding. It eventually got restored in the ''Remastered'' version. There would have been a mission mimicking the Iranian embassy siege of 1981, which brought the SAS to the public's attention for the first time. Unused sound files suggest the "Mile High Club" bonus mission was part of the main game and involved tracking down a nuclear arms dealer; it was moved to the end of the game as a bonus level, because it was far too difficult for what would have been the first or second real mission.
*** The American campaign was supposed to last for the whole game. Cut missions included piloting a Cobra gunship, being a Marine sniper (hence the [=M40A3=] being everyone's favorite sniper rifle in multiplayer but a complete no-show in singleplayer), using parabolic microphones to listen in on enemy chatter, checking dead bodies to identify al-Assad, and [[spoiler:controlling Jackson as he scavenges for anti-radiation equipment]].
*** A Russian campaign, completing the traditional [=CoD=] trifecta, was teased in very early screenshots, but almost nothing is known about it, implying it was cut very early.
*** The bad guys were originally supposed to be Chechen rebels fighting against the Russian state (Zakhaev is straight-up named for a prominent Chechen politician/guerilla), paralleling them with the al-Assad regime as two minority Muslims groups fighting much larger, more traditionally "westernized" superpowers, hence their mutual desire to use nuclear weapons to "even the odds". But when relations between Russia and its breakaway states worsened in real life, the baddies were reworked into "ultranationalists" with a hard-on for Soviet iconography, severing the connective tissue.
*** There were several maps that were intended for the multiplayer but ended up being cut, including "Hill", which looked to be a more direct interpretation of the singleplayer mission "Heat", and night-based versions of Ambush, Strike, District and Overgrown. The Variety Map Pack also had a pair of maps that were cut from it, "Favela" and "Invasion", which later ended up being put into ''Modern Warfare 2''.
** ''Modern Warfare 2'' originally had a level set on the International Space Station as it was invaded, but it was cut as it was felt to be too unrealistic and the assets ended up being recycled for the EMP cutscene.[[note]]The idea of combat on a space station would later be realized in the prologue to VideoGame/CallOfDutyGhosts.[[/note]] A level set in Los Angeles and another simply called "Roadkill" were also planned, but cut; the LA level was supposedly supposed to have the player riding a motorcycle, similar to the snowmobile from "Cliffhanger", which means that some of the code was probably salvaged for a similar sequence early in the following ''VideoGame/CallOfDutyBlackOps''.
*** Special Ops was born after the developers wanted to have regular campaign co-op like ''World at War'' had, but they found themselves unable to make the singleplayer levels both compatible with more than one player character and fun to play in the form they were supposed to appear. Special Ops as such mostly does with taking the existing maps for singleplayer and [[RemixedLevel remixing them]] for more challenge with less story that a second player can circumvent.
*** The game also had several cut weapons and perks. Most of the weapons were just ones from ''Call of Duty 4'' that didn't make the cut but [[DummiedOut had their files left in the game]] (the G36 [minus its sights, for some reason], R700, [=M40A5=], and M60 from ''[=CoD4=]'' can all be used in some singleplayer levels through hacking; the G3 was also used as a placeholder in some early pre-release footage, and there are still textures left over for others like the AK-74u, STG-44 and M14), though one weapon in particular was an entirely new addition, the L85 assault rifle - which ended up reworked into the L86 support weapon (indicated by the fact that its pickup icon is still an L85, and its maximum ammo is divisible by 30 rather than 100) Another new weapon that was simply cut rather than being reworked was the Remington 870 shotgun. Several perks also had weird and unique effects, like "Rearview" (replaced your minimap with a rear-view camera), "Dive" (let you dodge bullets by jumping), and "Challenger" (easier to kill in return for an experience multiplier); several ended up being worked into the game as an inherent ability ("Shellshock" would put a riot shield on the player's back; in the released game, putting away the riot shield always puts it on your back), as an attachment ("Thermal Vision" made enemies appear white-hot, presumably replaced by the thermal scope), or worked into another perk that made the cut ("Freerunner" would have let you mantle objects faster, which eventually became the Pro effect of Marathon; "Primary Stand" would have let the player use either weapon as an improved version of Last Stand, which instead became the deathstreak Final Stand; "Amplify" made enemy footstep sounds louder, worked into the Pro version of [=SitRep=]). Some were also revisited in later games in some form, such as "Spy Game" (which removed the red name or crosshair when an enemy player was close-by or targeting you) returning in ''[=MW3=]'' as Assassin, "Freefall" (which removed falling damage except for falling into pits or other clearly-inescapable areas) being worked into the effects of Lightweight in the ''Black Ops'' games, and "Mozambique" (which [[PunnyName let you fire all guns in three-round bursts]]) being combined with the eventual return of select-fire as an attachment in ''Black Ops II''.
*** The game had its own selection of cut maps as well, though not as many as the previous game. The cut maps include "Vertigo" (set on top of a building, likely cut for being too similar to Highrise), "Riverwalk", "Gulag" (a multiplayer conversion of "The Gulag" from singleplayer), and "Oil Rig" (a multiplayer conversion of "The Only Easy Day... was Yesterday"). One, however, "Fuel", ended up being released later on as part of the Resurgence Pack
** In spring of 2011, a lot of info about ''Modern Warfare 3'' was leaked, including concept art and the game's plot (you can read it [[http://kotaku.com/5801345/where-youll-go-how-youll-kill-and-who-will-die-in-modern-warfare-3 here]]). While most of the plot is similar to what made it into the final product, there are several interesting differences such as a mission set in the Kremlin, a mission as a U.S tank gunner in Germany, and [[spoiler:Sandman participating in the final mission to kill Makarov]]. The game also has cut lines for Price yelling out to Frost, the player character of the Delta Force missions, which alongside the fact that they actually made a model for him (used for Delta players in multiplayer and Spec Ops) indicates he was meant to take part in [[spoiler:rescuing the Russian President]], rather than being absent for no particular reason as he is in the released game.
*** Like ''Modern Warfare 2'', it had a lot of cut content in the multiplayer as well. Several weapons from ''[=MW2=]'' still have some remnant of themselves left in the game files, like the M240 (enough of it left over that the Wii version still has it), Vector (was even seen in some pre-release footage), TAR-21, M9 (again, still exists in a complete enough form that the player can see AI teammates use it and even pick it up from them if they die while using it), and several WWII-era weapons reusing files from ''World at War''. Several of the same cut perks from ''[=MW2=]'' are still referenced in the third game as well, including "Blackbox" (would have let the player use killstreak rewards longer), "Siege" (player couldn't move, but accuracy and recoil control would be boosted), as well as several unique ones such as using launchers as a perk as in ''[=CoD4=]'' rather than a separate weapon as they ended up being, an "Anytwo" perk that took up the first slot, but allowed you to use any two perks from any slots in the other two, an "Endgame" perk that gave the player four times their normal health [[TimedMission but made them drop dead after ten seconds]], and perk versions of some attachments, like Extended Mags and Akimbo. The game also had cut, early versions of some multiplayer maps, such as "Plaza" (reworked into Arkaden) and "Meteora" (later reworked into the DLC map Sanctuary). Spec Ops also had one cut mission that would have let the player(s) play through the defense of the Ferris wheel in Chernobyl from "One Shot, One Kill" in ''[=CoD4=]'', echoing the Spec Ops map from ''[=MW2=]'' that took the players backwards through "All Ghillied Up".