History EarlyInstallmentWeirdness / PokemonTheSeries

** Similarly, Serena's pajamas when we first see her wake up in her debut episode looked completely different from the one she would later wear to bed in later episodes.

* Sandstorm was inexplicably used as a damaging attack in Johto and Hoenn, like a Gust of a different type. From Sinnoh onwards, it was changed to a weather effect just like in the games, though James' Cacnea would still use it in a version of the original way (as a sandy version of Smokescreen and Haze, moves that Team Rocket's Pokemon use when needing to escape with their targets) for the remaining episodes he had it before giving it away

* The Kanto arc was really fond of reminding the viewer that there are only 151 Pokémon (though from the beginning, this was not true, as second-generation 'mon Ho-oh appears in the very first episode). When the second generation arrived, the number was updated to 251, with the excuse that those new 100 Pokémon had been "recently discovered", despite the fact that the anime many times would show those Pokémon being already known for decades or even centuries. From the third generation onwards this was dropped entirely, since it became obvious that new games would keep coming and the number of Pokémon was going to keep growing every 3-4 years, and the justification for the new Pokémon was simply that they lived in regions Ash had yet to visit. That said, in "Mystery at the Lighthouse", Bill does say that there may be no limit to the number of Pokémon out there.

* The Kanto arc was really fond of reminding the viewer that there are only 151 Pokémon (though from the beginning, this was not true, as second-generation 'mon Ho-oh appears in the very first episode.) When the second generation arrived, the number was updated to 251, with the excuse that those new 100 Pokémon had been "recently discovered", despite the fact that the anime many times would show those Pokémon being already known for decades or even centuries. From the third generation onwards this was dropped entirely, since it became obvious that new games would keep coming and the number of Pokémon was going to keep growing every 3-4 years, and the justification for the new Pokémon was simply that they lived in regions Ash had yet to visit. That said, in "Mystery at the Lighthouse", Bill does say that there may be no limit to the number of Pokémon out there.

* The Kanto arc was really fond of reminding the viewer that there are only 151 Pokémon. When the second generation arrived, the number was updated to 251, with the excuse that those new 100 Pokémon had been "recently discovered", despite the fact that the anime many times would show those Pokémon being already known for decades or even centuries. From the third generation onwards this was dropped entirely, since it became obvious that new games would keep coming and the number of Pokémon was going to keep growing every 3-4 years, and the justification for the new Pokémon was simply that they lived in regions Ash had yet to visit. That said, in "Mystery at the Lighthouse", Bill does say that there may be no limit to the number of Pokémon out there.

* A similar example is Pikachu, who was a bit of a {{Jerkass}} in the first episode (largely since he is shy, non-trusting of his brash new owner, and bitter about being unexpectedly evicted from the comfort of Professor Oak's laboratory) but mellows down considerably when Ash [[UndyingLoyalty earns his respect]]. Pikachu's early behaviour is seldom mentioned again. Pikachu was still feisty and occasionally irritable throughout Kanto (electrocuting Ash whenever he feels improperly treated, trying to kill Meowth at least once, etc), however future flashbacks and ''I Choose You'' use BackportedDevelopment to pretend that he became a complete NiceGuy after the first episode. Also, in the first few seasons, he was [[ArtEvolution a lot more chubby]], but slimmed down like ComicStrip/{{Garfield}} or [[Franchise/SuperMario Mario]], which was brought back as Pikachu's Gigantamax form.

* Snarky comments in general (both deserved and undeserved) were a staple of the anime's comedy back in its early days, but slowly faded out until the end of the ''Diamond and Pearl'' arc, where they were almost completely gone with a few notable exceptions. This can be observed the closest with Ash, who was a petulant and sometimes arrogant kid when he first started out in Kanto, [[CharacterDevelopment but eventually grew out of it from Hoenn onwards.]] Alola onwards brings back a little of the self-aware comedy and sarcasm, though remains a lot more idealistic than the early days.

* In the earlier seasons, characters, especially Gym Leaders, [[AdaptationPersonalityChange barely resembled their game counterparts]] in terms of personality. Kanto even [[AdaptationDyeJob changed their designs]][[note]]though Misty and Brock's changes [[ExposedToTheElements were somewhat justifiable]],[[/note]] while other seasons kept them a lot truer. At least one of the personality changes - Misty being {{tsundere}} - was [[CanonImmigrant added to the games]] (albeit {{downplayed|Trope}}). When Jasmine reappeared in Sinnoh she still kept her more aggressive anime personality and, to make it weirder, in her [[CharacterizationMarchesOn first episode]] she was closer to her ShrinkingViolet game portrayal.

** A more minor example is that in the earlier days of the show, several Gym Leaders were one-shot characters. Ash would simply show up at the gym and meet the Gym Leader, get his badge, and then leave, all in the same episode. The last Gym Leader where this happened was Wattson at the Mauville Gym, the third gym in the Hoenn League, though this was ultimately subverted in the episode where Ash and co. returned to Mauville City and met up with him again. Aside from that, the last Gym Leader to get this treatment was Chuck, the Cianwood Gym Leader, the fifth one in Johto. Nowadays, Ash never gets a gym badge in the same episode where the Gym Leader debuts. He will either spend their debut episode with them on a non-gym-related plot and have his gym battle in the next episode, or he will have a gym battle with them but lose and re-challenge the gym in a later episode. Another possibility is that he will challenge them to a gym battle in their debut episode, and the same battle will continue into the next episode where he will win it[[note]]Sootopolis, Striaton, and Virbank, with the Striaton one being notable for being 3 1-on-1s over the course of 2 episodes (Ash facing off against Chili's Pansear, Cress's Panpour, and Cilan's Pansage using Tepig, Pikachu, and Oshawott); the other 2 also had some non-standard conditions. Sootopolis started as a double battle, but once Ash had to use three Pokémon (Pikachu, Snorunt, and Corphish) to eliminate the first two Pokémon on Juan's side (Sealeo and Seaking), it switched to a single battle format to eliminate his remaining Pokémon (defeating Luvdisc, Whiscash, and Milotic using Grovyle, Corphish, Swellow, and Pikachu). Meanwhile, Virbank was a 3-on-''6'' battle, the only time Ash was allowed to use more Pokémon than his opponent (Roxie using Koffing, Scolipede, and Garbodor while Ash had Boldore, Unfezant, Leavanny, Pignite, Palpitoad, and Pikachu)[[/note]]. The only other single-episode Gym Leaders are more Ash doesn't battle in an official capacity like Agatha[[note]]Actually an Elite Four member, but she was the acting Viridian gym leader in her only appearance.[[/note]] and Cheren, or at all, like Drayden and Marlon (because by then, Ash already had his eight badges).

** In the initial stages of the Pokémon anime, the iconic Team Rocket trio--Jessie, James, and Meowth--had yet to be accompanied by a distinctive member who would eventually become an indispensable part of their crew: Wobbuffet. This quirky Psychic-type Pokémon, characterized by its blue hue and bobble-headed appearance, made its debut in an episode titled "Tricks of the Trade" (Episode 146 in the original Japanese release, and Episode 143 in the English adaptation) during the Johto Journeys saga. As Wobbuffet's presence grew, it rapidly garnered popularity for its uncanny ability to enliven Team Rocket's comedic escapades. Often emerging from its Poké Ball at the most inopportune moments, Wobbuffet's unpredictable nature consistently contributed to the trio's numerous defeats and misadventures.

* According to ''Literature/PocketMonstersTheAnimation'', ten-year-olds are considered legal adults. The anime doesn't go with this interpretation of the universe, however elements of this still snuck into Kanto episodes and made their mark.[[note]]One example involves Officer Jenny. One Jenny in Kanto arrested Ash, Misty, and Brock as part of a sting operation where she wore a Chansey hat in a zone where it was illegal to catch Pokémon to bait would-be poachers. A Jenny in ''Kalos'' detained Ash, Serena, and Bonnie [[FrameUp while they were being impersonated by Team Rocket]].[[/note]]
* In the episode "Island of the Giant Pokémon", Jessie's Ekans claims that all Pokémon are AlwaysLawfulGood; that is, they are ''never'' bad or evil of their own accord, [[MyMasterRightOrWrong but only when their trainer is]]. While this held true for a while, the appearance of a Teddiursa who steals food and frames Ash's Pokémon for doing so ([[KarmaHoudini and gets away with it]] until it is finally defeated by Ash and co. and evolves into Ursaring), a Spiritomb that Team Rocket tricks into believing Ash is descended from the one that sealed it away, an unusually mean Togepi that infiltrates Team Rocket's building, a gang of Litwick (who showed too much glee draining Ash, his friends and Team Rocket's life energy) and a Lampent that worked with said Litwick, a group of Malamar out to TakeOverTheWorld, and Jessie's Mimikyu (who joined Team Rocket purely out of hatred for Pikachu) disproves Ekans' point.

* The switch away from 4kids caused this in the long-run. For the first few seasons everyone had [[TheOtherDarrin different English voices]][[note]]Barring a few cases, Creator/JimmyZoppi as [[TheRival Gary Oak]], by then a guest character as his rivalry with Ash had ended, and Kayzie Rogers as Wobbuffet, were some of them. This also reinstated the original narrator Rodger Parsons after he had left early in Hoenn, and Creator/TedLewis eventually returned as [[BigBad Giovanni]] late in Sinnoh, and many, many more that are too numerous in number to list here, though including returns by Creator/JasonGriffith, Creator/TaraSands, and guest appearances by Creator/RachaelLillis and Creator/MaddieBlaustein[[/note]] and the anime was less true to the Japanese version. 4kids produced a lot of original music, including several soundtracks (such as ''Music/PokemonChristmasBash'') and the famous Pokéraps, which have mostly stopped since the dubbers changed. By contrast, the first couple of seasons used far more of the original Japanese music (which consists of arrangements of the games music), compared to most later episodes of the dub which usually have a completely new soundtrack outside a handful of the original edit's most signature tunes.

* Kanto and Johto stand out as they had their own original plots compared to the games. Future arcs at least try to adapt the villainous team to some degree, but the Original Series preferred to focus on the main Team Rocket trio of Jessie, James and Meowth instead of the team at large. Even in later episodes that ''do'' utilize more of the Team Rocket organization, they tend to consist of original characters such as Butch and Cassidy and Matori instead of adapt any of noteworthy members from the games (with all of the Executives from the Johto games being AdaptedOut, though many of their missions such as the Lake of Rage incident with the Red Gyarados were retained). The anime missed most of the major plot points of the first two generations and the Johto rival isn't even in the anime (aside from a cameo in the Japanese intro for ''The Legend of Thunder''[[note]][[TheRival Paul]] in Sinnoh may be an {{Expy}} of said rival, having a similar appearance and personality[[/note]]). This eventually led to trouble adapting elements of future games, which reference Team Rocket being split up during ''Red and Blue''/''[=FireRed=] and [=LeafGreen=]''.

* Very early on, characters could presumably keep as many Pokémon as they could carry. In Episode 11, "Charmander - The Stray Pokémon" Charmander's original owner Damien is shown carrying around a large pile of Poké Balls that presumably all contain Pokémon. It was revealed just two episodes later that trainers can only carry six at a time, the main rule in the games. This is later contradicted in Episode 43, "The March of the Exeggutor Squad" where Melvin, the Character of the Day, catches multiple Exeggutor and manages to keep them all on-hand throughout the episode.
** In early Pokémon episodes, when Pokémon are released, they are simply let out of their Poké Ball (or are able to leave when already out of it if the trainer no longer desires them, or wishes to set them free). However, later episodes show that when a Pokémon is released, they are ejected from their Poké Ball within a blue beam of light to indicate that they are no longer marked as owned and can be re-captured by another trainer. Since Damien didn't do this with his Charmander (it simply refused to go back to him) Ash shouldn't have been able to capture Charmander; his Poké Ball should have rejected the capture, but in early episodes this restriction wasn't established. Another later-added method of officially releasing a Pokémon is to destroy its Poké Ball; Jessie used this method to release her Dustox, as simply telling it to leave her didn't work.

* In his first regional transition - from Kanto to Johto - Ash didn't dump his entire team (sans [[SeriesMascot Pikachu]]) to start completely fresh, as became traditional from Hoenn on[[note]]This mostly took the form of having Pikachu, Bulbasaur, Charizard, and Squirtle, however, as Ash released Pidgeot shortly before he began heading for the Orange Islands, and when he got back to Kanto a while after he released Lapras in the Orange Islands, he let Snorlax stay with Professor Oak and put Tauros back as well. As a result of holding onto more Pokémon in Johto, he had to phase Charizard and Squirtle out early in his journey, eventually also putting Bulbasaur with Professor Oak later into it.[[/note]]. Also, Ash didn't change his hat or clothes and the female companion wasn't replaced (however, the original male companion, Brock came back for the Johto saga after his absence during the Orange Islands). For this reason, Kanto and Johto are often (especially on [[Website/TVTropes This Very Wiki]], as well as Bulbapedia) grouped together as "The Original Series", while every region from Hoenn on (except ''Journeys'' in Japan) gets its own [[NewSeasonNewName unique season/series name]].

* Some episodes of the first season would explicitly note the passage of time and the time of year. For example, Ash says he's been traveling for two months in "The School of Hard Knocks", while "The Ghost of Maiden's Peak" takes place at the end of the summer. Later seasons would usually be much more vague about how much time has passed, and the anime would eventually settle into taking place in a kind of perpetual early summer.
* Sandstorm was inexplicably used as a damaging attack in Johto and Hoenn, like a Gust of a different type. From Sinnoh onwards, it was changed to a weather effect just like in the games.

* Sandstorm was inexplicably used as a damaging attack in Johto and Hoenn, like a Gust of a different type. From Sinnoh onwards, it was changed to a weather effect just like in the games.

* Some episodes of the first season would explicitly note the passage of time and the time of year. For example, Ash says he's been traveling for two months in "The School of Hard Knocks", while "The Ghost of Maiden's Peak" takes place at the end of the summer. Later seasons would usually be much more vague about how much time has passed, and the anime would eventually settle into taking place in a kind of perpetual early summer.

* [[Anime/PokemonTheFirstMovie The]] [[Anime/Pokemon2000 first three]] [[Anime/Pokemon3 Pokemon movies]] all lacked a "World of Pokemon" intro at the very beginning of the movie, and the first Pokemon movie to begin with one, ''Anime/Pokemon4Ever'', had Brock narrate the World of Pokemon intro instead of the usual narrator, and the fourth movie's intro was reused in [[Anime/PokemonHeroes the fifth movie.]] It wasn't until ''Anime/PokemonJirachiWishMaker'' that all the Pokemon movies now started with a unique World of Pokemon intro.

* In the Japanese version of "The Battle of the St. Anne" Ash refers to the man he traded with as a "Gentleman". Aside from that Trainer Classes are ignored in the anime. Characters modeled after Trainer Class designs do appear at times, with one[[note]]Hoenn Schoolkid (male)[[/note]] [[https://bulbapedia.bulbagarden.net/wiki/Max becoming a companion]].[[note]]Albeit [[AnnoyingYoungerSibling underage]].[[/note]]

** The show also featured NewRulesAsThePlotDemands that reached [[MemeticMutation memetic levels]]. Sometimes if Ash needed to win an important battle, or the characters needed to escape a dangerous hazard, they'd just make something up on the fly and it would work. Emphasis on RuleOfFunny also led to some bizarre situations; {{visual pun}}s were emphasized and often the show would break its own logic in order to satirize the handheld games it was derived from. Later episodes stick far more closely to the rules of the games.

* Meowth's very backstory has been hit with this. The anime makes such a big deal about him being the only Meowth who can walk on their hindlegs. Early episodes portray all Meowth as quadrupedal, however the games always showed them bipedally and eventually the anime [[UniquenessDecay followed afterwards]]. Tyson's Meowth is bipedal but it's never commented upon. Meowth has an entire episode with a bipedal Alolan Meowth with no special attention given to it.

* Very early on, characters could presumably keep as many Pokémon as they could carry. In Episode 11, "Charmander - The Stray Pokémon" Charmander's original owner Damien is shown carrying around a large pile of Poké Balls that presumably all contain Pokémon. It was revealed just two episodes later that trainers can only carry six at a time, the main rule in the games.

* The episode "Island of the Giant Pokémon" has subtitles on the screen to translate what the Pokémon are saying (since the episode revolves around them trying to get back to their trainers) something that's never happened in any other episode as even in "Pikachu's Exciting Adventure!", the narrator translates what the Pokémon are saying.
* While Sabrina having PsychicPowers is ''not'' this, as many human psychics have shown up in later seasons, the way her powers are portrayed is: Sabrina can downright shrink people or turn them into dolls, making her a downright RealityWarper rather than a psychic (and that's before getting into how her powers gave her a LiteralSplitPersonality). Future human psychics have more grounded powers such as telepathy, precognition, and in some rarer cases, telekinesis and teleportation.
* [[Anime/PokemonTheFirstMovie The]] [[Anime/Pokemon2000 first three]] [[Anime/Pokemon3 Pokemon movies]] all lacked a "World of Pokemon" intro at the very beginning of the movie, and the first Pokemon movie to begin with one, ''Anime/Pokemon4Ever'', had Brock narrate the World of Pokemon intro instead of the usual narrator, and the fourth movie's intro was reused in [[Anime/PokemonHeroes the fifth movie.]] It wasn't until ''Anime/PokemonJirachiWishMaker'' that all the Pokemon movies now started with a unique World of Pokemon intro.

* [[Anime/PokemonTheFirstMovie The]] [[Anime/Pokemon2000 first three]] [[Anime/Pokemon3 Pokemon movies]] all lacked a "World of Pokemon" intro at the very beginning of the movie, and the first Pokemon movie to begin with one, ''Anime/Pokemon4Ever'', had Brock narrate the World of Pokemon intro instead of the usual narrator, and the fourth movie's intro was reused in [[Anime/PokemonHeroes the fifth movie.]] It wasn't until ''Anime/PokemonJirachiWishMaker'' that all the Pokemon movies now started with a unique World of Pokemon intro.
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** Dragonite is a standout case, starting off as an unknown beast in its first appearance (although this may be due to its unnaturally large size compared to the other Dragonite that later appear), then fully unveiled and owned by a trainer, but still clearly of elite sort in the Orange Island league, to being owned by Iris in ''Black and White'' but still a dangerously powerful and hard to control Pokémon, to being one of the first caught of Ash's ''Journeys'' team and fairly comical, but still very strong being able to beat Iris's Haxorus and beat down Leon's Dragapult who gave Dracovish trouble and beat Mega Lucario.

** In the same episode, Misty sends out her Goldeen against Team Rocket (despite it being a fish and therefore incapable of battling on land) to confuse and distract them, implying that deliberately sending out the wrong Pokémon battle to mislead your opponent is considered a valid and effective strategy. It would soon after be frequently reinforced that sending out the wrong Pokémon for the job is usually a serious blunder that can bring harm to the incompatible Pokémon and result in a quick and humiliating defeat for the trainer.

** In the same episode, Misty sends out her Goldeen against Team Rocket (despite it being a fish and therefore incapable of battling on land) to confuse and distract them, implying that deliberately sending out the wrong Pokémon battle to mislead your opponent is considered a valid strategy in a Pokémon battle. It would soon after be frequently reinforced that sending out the wrong Pokémon for the job is usually a serious blunder that can bring harm to the incompatible Pokémon and result in a quick and humiliating defeat for the trainer.

* Gyarados's UltimateAttack Dragon Rage is used in "Pokémon Shipwreck" when a whole group of them send the protagonists through a violent whirlpool. Dragon Rage was later {{Retcon}}ned to being a BreathWeapon, while the whirlpool concept was reused for Twister. Though both Arcanine and Dragonair have also used the whirlpool variant.

* Throughout the sixth episode, Clefairy holds a Moon Stone yet doesn't evolve. In "Electric Shock Showdown", Pikachu slaps away a Thunder Stone with his tail to a similar lack of effect. Later episodes have it so that simply touching an evolutionary stone induces evolution.

** Dragonite is a standout case, starting off as an unknown beast in its first appearance (although this may be due to its unnaturally large size compared to the other Dragonite that later appear), then fully unveiled and owned by a trainer, but still clearly of elite sort in the Orange Island league, to being owned by Iris in ''Black and White'' but still a dangerously powerful and hard to control Pokémon, to being one of the first caught of Ash's ''Journeys'' team and fairly comical, but still very strong being able to beat Iris's Haxorus and beat down Leon's Dragpult who gave Dracovish trouble and beat Mega Lucario.

* The original series had plenty of characters who were completely and utterly arrogant and mean towards Ash, making the setting a borderline WorldOfJerkass. Characters of the Day would be very antagonistic (especiaaly those in the early episodes, such as Samurai, Giselle or AJ) while Gym Leaders were rude and sometimes downright unprofessional (such as Lt. Surge insulting Ash and Pikachu while his Raichu was so brutal the Pokemon it defeated had to be hospitalized, Erika's staff banning Ash from entering her gym just because he badmouthed her perfume, and Sabrina being a downright horror movie villain who either shrunk people or turned them into dolls with her psychic powers). Not even the main characters escaped this, as Misty and Brock were far more likely to demean Ash for his problems than helping or even sympathyzing with him. In later episodes, Ash is treated with ''far'' more respect by the countless strangers he meets and anyone who dislikes him usually evolves into a recurring rival and/or villain later on (Paul, for example), and Gym leaders are much nicer and behave in a more professional manner.

* The anime was originally supposed to take place on a futuristic Earth. According to [[Literature/PocketMonstersTheAnimation two supplementary books]] made by Creator/TakeshiShudo, the original plot for the [[Anime/Pokemon3 third film]] would have been based around how the Pokémon drove the original animals out. "The School of Hard Knocks" mentions Misty always wanting to visit France. Other real places mentioned in the anime include England, Guyana (where Mew was hidden), and Hollywood (though apparently not America's Hollywood since it's in Kanto). Jessie's MissingMom Miyamoto was last seen looking for Mew in the Andes mountains according to ''[[Radio/PokemonTheBirthOfMewtwo The Birth of Mewtwo]]'' radio drama. But [[EarthDrift France and Hollywood at least have since been replaced by brand new places that are based on them]], such as [[VideoGame/PokemonXAndY Kalos]] and [[VideoGame/PokemonBlack2AndWhite2 Pokestar Studios]]. Holiday episodes are also rarer now (with a later statement that [[ComicBookTime the series is set in an eternal early summer]] limiting holidays outside this time period), and when they do appear [[YouMeanXMas they use counterpart holidays]] instead of the actual holidays (compare the infamous Kanto ChristmasEpisode to the Kalos one[[note]]which aired in Japan a month after Christmas[[/note]]).

** The episode "Bad To The Bone" has Jessie try to catch Otoshi's Doduo with a Poke Ball despite the fact he already owns it. In later episodes, when a character tries to catch a Pokémon under the ownership of someone else already, the Ball refuses to work, so Jessie should've known she's wasting her time. But the ball was knocked away by Marowak's bone club, so we don't know what would've happened. Interestingly, this is averted in the Japanese ''[[Radio/PokemonTheBirthOfMewtwo The Birth of Mewtwo]]'' CD drama, in which Sakaki/Giovanni steals a defeated Trainer's Magmar.

* The switch away from 4kids caused this in the long-run. For the first few seasons everyone had [[TheOtherDarrin different English voices]][[note]]Barring a few cases, Creator/JimmyZoppi as [[TheRival Gary Oak]], by then a guest character as his rivalry with Ash had ended, and Kayzie Rogers as Wobbuffet, were some of them. This also reinstated the original narrator Rodger Parsons after he had left early in Hoenn, and Creator/TedLewis eventually returned as [[BigBad Giovanni]] late in Sinnoh, and many, many more that are too numerous in number to list here, though including returns by Creator/JasonGriffith, Creator/TaraSands, and guest appearances by Creator/RachaelLillis and Creator/MaddieBlaustein[[/note]] and the anime was less true to the Japanese version. 4kids produced a lot of original music, including several soundtracks (such as ''Music/PokemonChristmasBash'') and the famous Pokeraps, which have mostly stopped since the dubbers changed. By contrast, the first couple of seasons used far more of the original Japanese music (which consists of arrangements of the games music), compared to most later episodes of the dub which usually have a completely new soundtrack outside a handful of the original edit's most signature tunes.

* There were many instances of non-Pokémon animals, one of the most infamous examples being the mongoose Gastly turns into in "[[BizarroEpisode The Ghost of Maiden's Peak]]" and fish in an aquarium in the Cerulean Gym in the seventh episode. While some animals (usually smaller ones such as butterflies and starfish) still occasionally appear in the anime, they're much, much rarer and have largely been replaced by Pokémon. The large majority of the later appearances of real world animals are often of fish ... as food.

* The Kanto arc was really fond of reminding the viewer that there are only 151 Pokémon. When the second generation arrived, the number was updated to 251, with the excuse that those new 100 Pokemon had been "recently discovered", despite the fact that the anime many times would show those Pokemon being already known for decades or even centuries. From the third generation onwards this was dropped entirely, since it became obvious that new games would keep coming and the number of Pokemon was going to keep growing every 3-4 years, and the justification for the new Pokemon was simply that they lived in regions Ash had yet to visit. That said, in ''Mystery At The Lighthouse!", Bill does say that there may be no limit to the number of Pokémon out there.

* Tons upon tons of Pokemon fall into UniquenessDecay as the franchise goes on, starting off as mysterious uncatchable entities to regular occurances often seen with trainers:

** Several mythical or legendary Pokemon are introduced in the movies as otherworldly and often posess more sapient abilities like being able to talk human language, only to reappear in the show itself as standard if rare Pokémon. Compare the talking Shaymin of ''Giratina and the Sky Warrior'' to Mallow's in the ''Sun and Moon'' series, which acts [[FurryConfusion no differently]] from the other baby-like Pokemon of the main group.

* In Episode #2, [[Recap/PokemonS1E2PokemonEmergency "Pokemon Emergency!"]], Pikachu's injuries from battling the Spearow flock are treated as life-threatening, and there is real worry on Ash's part (and even Nurse Joy's) that Pikachu might not make it. The franchise would soon phase out any suggestion that Pokémon could be hurt ''that'' seriously by fighting other Pokeémon; moreover, while battles still do sometimes result in Pokemon needing relatively extensive medical treatment (up to and including hospitalization), the worst that usually happens to them later is dizziness and/or fatigue.
* The episode "Island Of The Giant Pokémon" has subtitles on the screen to translate what the Pokémon are saying (since the episode revolves around them trying to get back to their trainers) something that's never happened in any other episode as even in ''Pikachu's Exciting Adventure!", the narrator translates what the Pokémon are saying.

** Dragonite is a standout case, starting off an unknown beast in its first appearance, then fully unveiled and owned by a trainer, but still clearly of elite sort in the Orange Island league, to being owned by Iris in ''Black and White'' but still a dangerously powerful and hard to control Pokémon, to being one of the first caught of Ash's ''Journeys'' team and fairly comical, but still very strong being able to beat Iris's Haxorus and beat down Leon's Dragpult who gave Dracovish trouble and beat Mega Lucario.