[[quoteright:350:[[Franchise/StarTrek https://static.tvtropes.org/pmwiki/pub/images/eveolutionaryretcon_7735.jpg]]]]
[[caption-width-right:350:On the left, Commander Kor in "[[Series/StarTrekTheOriginalSeries Errand of Mercy]]." On the right, Commander Kor in "[[Series/StarTrekDeepSpaceNine Sword of Kahless]]," twenty-five years later (105 in-universe).]]
->''"And what is with the Klingons?\\
Remember in the day?\\
They looked like Puerto Ricans and they dressed in gold lamé\\
Now they look like heavy metal rockers from the dead\\
With leather pants and frizzy hair and [[RubberForeheadAliens lobsters on their heads]]"''
-->-- ''The USS Make Shit Up'', '''{{Music/Voltaire}}'''

Over the course of time, advances in special effects technology and make-up techniques can allow a series to have bigger and better creatures and monsters. Often, the original version of a creature might not have been that cool or interesting, and so a new model was established using the more advanced technology. In other cases, technological advances can't be credited for the retcon: sometimes a creature's look will change as a series progresses due to ArtEvolution.

This is often seen in fantasy or Sci-fi media.

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!!Examples:

[[foldercontrol]]

[[folder:Comic Books]]
* ''Franchise/GreenLantern'': All H'lvenites portrayed since the reboot have been drawn realistically, rather than the "funny animal comic book" style that Ch'p was traditionally drawn in. They're also about the same size as a squirrel, instead of being the size of a three-year-old human child.
[[/folder]]

[[folder:Films -- Animated]]
* The glimpses of Legolas (who has been DemotedToExtra) in the Rankin & Bass version of ''WesternAnimation/TheReturnOfTheKing'' reveals an appearance retcon for the Elves compared to their appearance in ''WesternAnimation/TheHobbit''. Aside from the StockFootage of Thranduil from ''WesternAnimation/TheHobbit'', the appearance of the Elves has been revised to have them looking much more like humans (as one can tell from Legolas' few appearances).
[[/folder]]

[[folder:Films -- Live-Action]]
* The xenomorphs from the later ''Franchise/{{Alien}}'' films are much more insectile and predatory than [[Film/{{Alien}} the original film]]'s man in a suit version.
** Justified in-universe in some of the films. ''Film/Alien3'' had a smaller, more quadrupedal alien that had come from a dog rather than a human. ''Film/AliensVsPredatorRequiem'' had one alien come from a predator. ''Film/AlienResurrection'' had all the aliens contaminated by the cloning method used to create the queen from the dead Ripley.
** In the non-justified examples, it wasn't all due to effects technology improving. ''Film/{{Aliens}}'' was not made long after the first film, they simply thought the redesign [[RuleOfCool looked better]].
* ''Film/JurassicParkIII'''s raptors are brightly colored and frilled as a nod to the [[ScienceMarchesOn then-recent discovery that they had feathers]].
* By the third entry in Creator/PeterJackson's ''Film/TheLordOfTheRings'' series, he'd decided he wasn't a fan of the "witch noses" on certain orcs in the previous films. As a result, none of ''[[Film/TheLordOfTheRingsTheReturnOfTheKing Return of the King]]'''s orcs sported long, pointy noses.
[[/folder]]

[[folder:LiveActionTV]]
* In ''Series/DoctorWho'':
** The original Daleks were clunky and, because they were mounted on tricycles, had difficulty with rough terrain. [[WeaksauceWeakness And stairs? Forget about it.]] [[spoiler: Until their very last appearance, anyway - but they couldn't fire at the same time until the new series.]] CGI allows the new series to feature flying Daleks who are capable of traversing stairs and ''interstellar space'' without trouble. Heck of an upgrade there. This is somewhat justified, though, sometimes in-setting, in that the Dalek casings are technological constructs, and a technologically brilliant species ''would'' surely upgrade them from time to time. This even permits the occasional tongue-in-cheek episode where a Dalek built with the best available material comes out looking quite clunky or archaic -- although somehow it'll usually have late-model-style capabilities.
** The Cybermen are famous for their repeated redesigns, which is again fairly plausible in a species whose whole concept is ruthless self-augmentation. The major shifts are from the original "Tenth Planet" look with visible human body parts to the all-metal appearance of their second story "The Moonbase"; the shift to the "square-headed" silhouette in "The Invasion"; and the "baggy" eighties look from "Earthshock". But practically every story saw some tweaking to the design. The 21st-century series introduced another, even more robot-like look, and there was then a further redesign in the Moffat era to remove the "Cybus" branding that marked the Davies-era Cybermen as alternate-universe. The Moffat-era design was stated by the designers to be a CallBack to this: the Cybermen never remain the same for too long. Upgrade in progress!
** Another ''Series/DoctorWho'' example: the Macra. Old series Macra look like [[http://i133.photobucket.com/albums/q55/ashtonlamont/mo_ma01_Macra_400.jpg this.]] New series Macra look like [[https://static.wikia.nocookie.net/tardis/images/d/d9/The_Macra_(Gridlock).jpg this.]] This is explained by there being 5 billion years between them, during which time they have evolved from intelligent beings with a huge empire into mindless creatures living on the poisonous fumes of the New New York motorway.
** The Silurians in the old series were done with rather clunky (and practically immobile) masks. The new ones are still created with makeup, but it's far more sophisticated and lifelike. However, the old ones were more ''alien'', featuring sucker-like mouths and three eyes. The new ones look more like green, scaly humans. This is acknowledged in-show as being different subspecies.
** The Sontarans as they appeared in 1973 and 1975 did not have the most expressive faces. This was improved somewhat in 1978, then took a big step back in 1985, looking less realistic than even their first appearance. For BBV's ''Shakedown'', the appearance of the Sontarans had to be modified to avoid legal complications with the BBC, which owned the design of the creatures, but even that was an improvement over the 1985 incarnations. Ultimately, the Sontarans were refined for their return in the new series, allowing for unlimited expression.
** The Ice Warriors, reptilians in battle armour, were faithfully updated for the new series, allowing for more expression in the one part of them that remains exposed, their lower face. When an Ice Warrior removed their helmet, their head was depicted using some impressive CGI.
** The Zygons as seen in the classic series were obviously PeopleInRubberSuits. Despite being produced nearly 30 years later, BBV's reduced budgets meant that their Zygons looked worse than the originals. The new series retained their iconic shape while updating them, making them appear more fleshy with more expressive faces.
** Following their appearance in Series 1 of the revival, the Slitheen family of Raxacoricofallapatorius were reprised in the SpinOff ''Series/TheSarahJaneAdventures'', in which they were depicted with new costumes which gave them more expressive faces, allowing them to bare their teeth and so make them somewhat more fearsome. It were these costumes that were used when the species eventually came back for a cameo in "The End of Time".
* In ''Series/BuffyTheVampireSlayer'', Oz's wolf form went from an animatronic to a much sleeker full-body skunk-wolf suit.
* ''Franchise/StarTrek'':
** The Klingons in the original ''Series/{{Star Trek|The Original Series}}'' series were basically swarthy HumanAliens, but advances in make-up technology allowed them to become one of the best (and most believable) examples of RubberForeheadAliens. This example is notable in that Creator/GeneRoddenberry always claimed that the "new" Klingons were how they would have looked back in the 1960s if it had been possible at the time - he considered the new Klingon look to be how the old ones ''always'' did but [[DirectLineToTheAuthor there just wasn't the budget to show it]]. (The original Trek often didn't have the budget even when it had the means. Why'd the old-school Romulans wear helmets? Easier than making custom pointy ears for everyone - which is also why several Vulcans wore the same helmets in "Amok Time"!) In-universe, the difference didn't exist until attention was called to it in an episode where the ''Series/StarTrekDeepSpaceNine'' crew went to the past. Then ''Series/StarTrekEnterprise'' comes along, with pre-TOS Klingons looking like the "new" ones! Yes, we ''do'' at long last get an explanation.
** Confusing matters further is yet another new Klingon look appearing in ''Series/StarTrekDiscovery'', which looks nothing like the TOS style and only partly like the now-familiar style from every other series. The familiar forehead crest has developed into a series of ridges and bulges that now cover the entire cranium, which is now elongated to the rear. They also now have dark, bluish skin, and are commonly seen as bald (though it seems to be a contemporary style, as a few Klingons are seen with hair).
** The Borg also received an upgrade in ''Film/StarTrekFirstContact'', losing the chalk-white skin in favor of glistening, apparently decaying flesh to make them like outright cyber-zombies. They were given more implants on their bodies, and their ships were redesigned. They also got a major design change between their first and second appearances in ''Series/StarTrekTheNextGeneration''. The second features a much more modular design to how the prosthetics were done, allowing more drones to be made up than the individual custom jobs used in the first appearance. The chalk-white skin was largely to save on labor in makeup, and techniques using quick airbrushing allowed the hard bits (like deeply shadowed eyes) to be done fast by a small number of highly trained makeup people after more generally trained ones did the bulk of it, again so that more drones could be made up.
** Romulans had the same make-up as Vulcans in TOS and some early TNG. In later seasons of TNG and all following series, they have a distinctive V-shaped ridge on their foreheads. However it seems that this retcon did not apply to all: there are later examples of Vulcans and Romulans passing as each other, suggesting there are minorities among both who look like the other. Which makes sense, since biologically they're the same race. ''Series/StarTrekPicard'' would later establish that the ridged-forehead Romulans are "Northerners" on their homeworld.
** Trills are kind of a reverse example by ''Star Trek'' standards: they first appeared in the TNG episode "The Host" as a [[RubberForeheadAliens Rubber Forehead Alien]]. By the time they reappeared in [=DS9=], they lost the forehead and had spots, being less complicated and arguably something TOS could have done (all done because they had StatuesqueStunner Terry Farrell play the Trill in question and thought the original make-up took away from her looks).
** In the unaired TOS pilot "The Cage", Talosians had a MyBrainIsBig appearance, which was repeated in the "Menagerie" two-parter. Fast-forward to ''Series/StarTrekDiscovery'', and Talosians now have a more organic RubberForeheadAliens appearance (still with large craniums) and more elaborate costumes. Obviously, all the actors are different as well (given that the originals have all passed).
** Between ''Discovery'' and ''Series/StarTrekStrangeNewWorlds'' (plus an episode of ''Short Treks''), the entirety of the TOS-era aesthetic is now being treated under this trope to an extent, as the more-modern tech aesthetic of the former has been carried over to the latter's depictions of the ''Enterprise'' and its interiors. With the series having diligently practiced ZeerustCanon in the past when prior installments revisited the era, it remains a controversial decision with fans, even with ''Strange New World's'' positive reception. However, the retcon doesn't appear to be in full effect, as ''Picard'' would go on to depict a Constitution-class ship in a fleet museum that still retains the TOS aesthetic, suggesting the retcon isn't definite and can still be considered artistic license.
[[/folder]]

[[folder:VideoGames]]
* The Covenant from the ''Franchise/{{Halo}}'' series have become more life-like and more scary-looking as computer animation technology has improved:
** In general, Elites have become stouter with ever more ornate armor, with ''VideoGame/HaloReach'' particularly notable for its wide array of heavy ornate armor. That said, while post-''Reach'' games have given Elites even more imposing physiques, they've also somewhat pared down their armor; while Elites still get to keep the fancy helmets, a lot of them don't even wear sleeves anymore! Additionally, their skin has become a lot lighter.
** With the occasional exception, the Grunts have trended towards reddish eyes and rough, almost spiky exoskeletons.
** Brutes have cycled back and forth between various combinations of hairy, shaven, [[ExposedExtraterrestrials naked]], and armored, likely as a response to available graphics technology. Interestingly, they started off as hairy in ''VideoGame/{{Halo 2}}'', became shaved in subsequent games, and came back even more hairy in ''[[VideoGameRemake Halo 2: Anniversary]]''. One trend that ''has'' stayed consistent is their faces becoming ever more ape-like as their snouts and noses have become less and less pronounced, to the point where their faces are currently almost flat.
** Jackals started off as dark-skinned in ''VideoGame/HaloCombatEvolved'', but have subsequently been some shade of yellowish/orangish/reddish. Additionally, their armor has become thicker and more pronounced.
** The Drones' exoskeletons have generally become smoother and more visibly segmented in each new appearance.
** Interestingly, WordOfGod is that almost every Covenant phenotype and armor design seen throughout the franchise are equally canon, the former explained as different subspecies/racial groups and the latter as differences in manufacturing (the Covenant canonically avoid things like standardization and mass production); this means it's perfectly fine lore-wise to depict, for example, ''VideoGame/{{Halo 3}}''- and ''VideoGame/{{Halo 4}}''-style Elites standing side by side.
* ''Franchise/DragonAge'':
** ''VideoGame/DragonAgeII'''s qunari sport horns in order to differentiate them from the other races. The official explanation as to why the qunari seen in ''Origins'' don't have horns is that the qunari who are naturally born hornless, such as Sten and the members of his squad, are considered special and are given special tasks, such as scouting foreign lands, while the other qunari seen in ''Origins'' are [[DefectorFromDecadence Tal-Vashoth]] mercenaries who typically remove their horns when they leave the qunari.
** The Darkspawn have also changed: hurlocks appear a few shades lighter, smoother-skinned, and with blunter teeth in the sequel, while genlocks become more gorilla-like than goblin-like, and emissaries stop being other species of darkspawn with magic and become something akin to a hybrid of an arcane horror from the first game and the Architect from the ''Awakening'' DLC.
* In the first ''Franchise/{{Metroid}}'', due to graphical limitations, Kraid and Ridley are both the same size as Samus. By the time ''Super Metroid'' came around, Kraid was two rooms high, and Ridley was at least three times the size of Samus. ''VideoGame/MetroidZeroMission'' retcons the ''Super'' design into canon.
** ''VideoGame/SuperMetroid'' also adds a "fake Kraid" that's slightly taller than Samus and much easier to kill outside of the real Kraid's room: this is both a reference to the size difference in the earlier games as well as the fact that the NES game had multiple Kraids, but only one of them was the real one.
** Throughout the ''Videogame/MetroidPrimeTrilogy'', the Space Pirate models vary greatly, gaining a separating lower jaw and going from two to four eyes. Partially justified as the Pirates are genetically altering their troops (with varying levels of success) to enable them to conquer the galaxy.
* {{Inverted}} in ''VideoGame/DeusExHumanRevolution'', a prequel set approximately 30 years before the original ''VideoGame/DeusEx'', has mechanical augmentations that are significantly more advanced and useful than the un-lifelike ones in ''Deus Ex''. The excuse is that this is right before a great collapse which occurs prior to the beginning of ''Deus Ex'' and before the rise of nano augmentations.
* Practically every memorable demon in the ''VideoGame/{{Doom}}'' series was completely redesigned for ''VideoGame/{{Doom 3}}''. Most of these redesigns made the demons appear much scarier and more formidable opponents for the player. The original imp, for example, was a large, brown creature with spikes on its shoulders that would slowly advance towards the player while hurling fireballs at them. The new imp is a slimmer grey creature with no spikes and ten eyes on its head that is capable of climbing walls and has incredible jumping ability that allows it to clear the distance across an entire room in a single leap and generally attacks with a much more aggressive style. ''VideoGame/Doom2016'' then took things full-circle by then re-redesigning several demons to look closer to their original appearances, though a few are left as they were; e.g. the Hell knight looks like it did in ''Doom 3'' while the Baron, which was left out of the third game, still has its classic appearance.
* ''Franchise/TheElderScrolls'' series has surprisingly averted this for the most part, despite major overhauls to the graphics with each new game release. Most of the races and creatures that appear in each game have kept the same look, with only improvements in the ''quality'' of their appearance, not to the appearance itself. However, there are two major exceptions:
** One area where it has been played straight is with the [[LizardFolk Argonian]] race. ''[[http://www.uesp.net/wiki/Arena:Argonian#Argonian Arena]]'' displayed them as gray skinned humanoids. Two games later, ''[[http://www.uesp.net/wiki/File:MW-npc-Big_Head.jpg Morrowind]]'' turned them into bird-legged, iguana-looking people. ''[[http://www.uesp.net/wiki/File:OB-npc-Amusei.jpg Oblivion]]'' returned them to more traditionally bipedal dinosaur-looking people. Finally, ''[[http://www.uesp.net/wiki/File:SR-race-Argonian.jpg Skyrim]]'' has them looking like predatory ''velociraptor'' looking people (they use the same model as other races, apart from the reptilian head and tail). This evolution is ostensibly justified in-universe by the fact the Argonians worship the "Hist," a race of [[WiseTree sentient trees]] in their homeland of Argonia (or "Black Marsh"). Hatchling Argonians drink the sap from the Hist that changes them physically. After the events of the [[VideoGame/TheElderScrollsIVOblivion Oblivion Crisis]], it is believed that the Hist have been strengthening the Argonians, turning them into more formidable warriors over time.
** A lesser example would be the Khajiit, a CatFolk race. In ''[[http://www.uesp.net/wiki/Arena:Races#Khajiit Arena]]'' and ''[[http://www.uesp.net/wiki/Daggerfall:Races#Khajiit Daggerfall]]'', they look like a race of hardy and fair-skinned men that [[LittleBitBeastly hardly (if at all)]] resemble their supposed feline ancestors. In ''[[VideoGame/TheElderScrollsIIIMorrowind Morrowind]]'', ''[[VideoGame/TheElderScrollsIVOblivion Oblivion]]'', and ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'', they're BeastFolk that resemble humanoid tigers. The {{retcon}} here isn't that they turned into different forms like the Argonians, but rather it's a part of their biology; by the waxing and waning of the [[AlienSky two moons]] Masser and Secunda, the children born to a Khajiit can range in appearance from a small house cat to a fair-skinned man to a cat-man to a feline big enough to be ridden as a beast of battle.
** In Morrowind, the anatomy of Argonians and Khajiit featured non-humanoid legs and feet, resembling the hind legs of a quadruped and making it impossible for them to don shoes and boots. In Oblivion and Skyrim, their lower appendages became humanoid in appearance
* ''VideoGame/DarkOrbit'': Most enemies and some ships have gotten this at some point, some repeatedly.
* Some [=NPCs=] in ''VideoGame/MapleStory'' get really nice-looking design revamps. Additionally, every time the explorers get a revamp, skills that don’t change suddenly look really nice.
* Mileena from ''Franchise/MortalKombat'' was given a minor [[http://www.giantbomb.com/images/1300-2741300 redesign]] in ''VideoGame/MortalKombatX''. Previously, she had MoreTeethThanTheOsmondFamily, but they've been downplayed. She was given lips and normalish front teeth while the giant mutant teeth are now on the sides of her mouth, giving her what appears to be a GlasgowGrin. However, this isn't a technological upgrade, but most likely a designer realizing Mileena's previous mouth would have given her a ''massive'' speech impediment without lips to form half her words.
* ''Franchise/TheLegendOfZelda'':
** The [[FishPeople Zora]] are all over the place in their character design. In early games, they were monstrous, AlwaysChaoticEvil fishmen who attacked you from any body of water. ''[[VideoGame/TheLegendOfZeldaOcarinaOfTime Ocarina of Time]]'' redesigned them as more humanoid, blue creatures with fins attached to their limbs and a tail at the back of their head, while portraying them as an NPC race instead of an enemy. ''[[VideoGame/TheLegendOfZeldaOracleGames Oracle of Ages]]'' brought back both the monstrous enemy Zora of the 2D games and the friendly Zora of ''[=OoT=]'' and established them as two separate races, distinguishing the former as "River Zora" and the latter as "Sea Zora". ''[[VideoGame/TheLegendOfZeldaTwilightPrincess Twilight Princess]]'' redesigned the Sea Zora again, giving them different colours than the plain blue of ''[=OoT=]'' Zora as well as giving them somewhat more humanlike faces. ''[[VideoGame/TheLegendOfZeldaALinkBetweenWorlds A Link Between Worlds]]'' brought back the River Zora, although it averts their former AlwaysChaoticEvil depiction and bizarrely seems to imply that their queen, Oren, is a descendant of Princess Ruto[[labelnote:spoilers]]All of the Seven Sages in ''ALBW'' are expies of the ones in ''[=OoT=]'', and are also stated to be descended from them. As the only explicitly non-human Sage in ''ALBW'', Oren is the only plausible candidate for Ruto's descendant, with the only other non-human ''[=OoT=]'' Sage Darunia's most likely descendant being the AmbiguouslyHuman Rosso.[[/labelnote]]. ''[[VideoGame/TheLegendOfZeldaBreathOfTheWild Breath of the Wild]]'' redesigned the Sea Zora again, this time making them look more like [[SharkMan Shark Men]].
** The [[BirdPeople Rito]] took a huge leap on the SlidingScaleOfAnthropomorphism between ''[[VideoGame/TheLegendOfZeldaTheWindWaker The Wind Waker]]'' and ''Breath of the Wild''. In the former, they are said to be descended from the aforementioned (Sea) Zora who rapidly evolved from aquatic to avian. They are mostly LittleBitBeastly {{Winged Humanoid}}s whose main avian traits are their ducklike beaks and on-again-off-again appearing wings. In the latter, they are more like anthropomorphic birds with very few humanlike traits. They also appear to coexist with the Zora, and are nowhere implied to be related to them.
[[/folder]]

[[folder:WebVideo]]
* ''WebVideo/FranceFive'': Several costumes were upgraded over the series. Namely, Margarine, the France Five suits, and France Robo itself. The episode 1 costumes reappear in flashbacks during episodes 3 and 6, explained away as prototypes for the current models which now have always been there.
[[/folder]]
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