The original short had crude animation and an even cruder art style (dubbed by creator Pen Ward as having a pre-school vibe), Finn was named Penn, Lady Rainicorn did not speak Korean but some sort of coo-ing language, and Jake somehow could connect his mind to the Internet. Aside from Jake and Abraham Lincoln, all characters have different voice actors in the series (Jeremy Shada's older brother, Zack, voices Finn/Pen, Paige Moss voices Princess Bubblegum, John Kassir of Tales from the Crypt fame voices Ice King, and Dee Bradley Baker, who would become a regular voice actor in the main series, voices Lady Rainicorn). This is also the only time where Princess Bubblegum is a Damsel in Distress. Despite all of this, the episode "Sons of Mars", in which Lincoln recognizes Finn, implies that the pilot is still broadly canon to the show’s continuity.
In "Slumber Party Panic", Finn and Jake must keep the invasion of candy zombies secret because, according to Princess Bubblegum, the candy people explode if frightened. Not only is this fact never mentioned again, it has been disproved several times. Then it happens again in a season 6 episode!
In general, early episodes, mostly the first season, runs on Negative Continuity: Finn discovers his fear for the ocean despite not showing the slightest fear in a previous episode where he was on the beach, Finn and Jake get wizard magic and learn ice ninja abilites but don’t retain them afterward, they adopt a pie throwing robot that is never seen again note at least until season 4, where it’s handwaved that they forgot about him during a hide and seek game. Another episode ends with the heroes brainwashed by a giant worm,.. Later the show falls into Continuity Creep after the second season finale, gaining a flowing narrative, developing several sequel episodes and regularly having many continuity nods.
The first season also has Finn and Jake with practically opposite personalities and plot roles to their later development, with Finn as a well-intentioned but excessively-violent Blood Knight and Jake with a very parental elder-brother relationship towards him. It didn't take long for Finn to become much more morally principled and Jake to turn into an irresponsible Manchild.
There's also the show's title card appearing at the end of some early episodes.
The pilot episode had both Gumball and Darwin Watterson look nothing like how they do in the series proper (Darwin was CGI instead of 2D animation, and Gumball's design was radically different). Both also had different voice actors, and the less said about the earlier designs of the other characters, the better.
In the series proper, some characters had slightly or completely different personalities in season 1 than in season 2. Darwin started off being just as dumb (if not dumber) as Gumball, but eventually became the slightly naive voice of reason. Alan the balloon became an extremely Nice Guy in season 2 when, in the first season, he could be just as antagonistic toward Gumball and Darwin as the other students at the school. Then there's Sussie the chin puppet, who was a relatively normal student (who tended to drool on everything and always chewed with her mouth open, to emphasize the fact that she was a chin puppet), but became a bizarre Cloud Cuckoo Lander in season 2.
The first season's episodes were mostly centered on Gumball, his family, and their trials and tribulations in life; some episodes were Mundane Fantastic while others were no different than what you would normally see in a family sitcom. Later episodes do still have these type of episodes, but are significantly Denser and Wackier, more darkly comedic, and often involve a lot of Genre Roulette. There's also a greater focus on Gumball's classmates.
In the first season, the first ten episodes or so were animated slightly differently from the later episodes. All the episodes have mixed media, with CGI dinosaurs mixed in with claymation balls of clay, 2D flowers, and ghosts. However, the animations of the 2D characters became slightly more jerky and generally cartoony than the first episode's more lifelike motions. Gumball's body also changed in form slightly, with his fangs rounded and his eyes slightly smaller than before. All of this was changed by the first season finale, as the animations in the last two episodes seemed less jerky and more lifelike, along with Gumball's fangs being sharp again and his eyes being bigger.
The first season featured unrefined character designs, and supporting characters (such as Bobert, Leslie, Clayton, Alan, and Anton) had their voices change erratically from episode-to-episode.
Miss Simian in season 1 was blockier, shaded gray, had a scratchier voice. Starting in season 2, Miss Simian's computer animation was more refined, she had a somewhat lower, yet still screechy voice, and now wears a pink dress.
Mr. Small did not look or sound like a stereotypical hippie in season 1. In season 1, he had a slight Southern accent, was more of a parody of touchy-feely guidance counselors, and, as seen in "The Meddler," acted like a Drill Sergeant Nasty when it came to cheerleading auditions.
The Watterson children were allowed far less independence in the first season: Excepting emergencies and sneaking out, the kids are chaperoned everywhere outside school and their own neighborhood. In "The Responsible", they're allowed to stay home without a babysitter only out of desperation, and Nicole concludes even that was a huge mistake. In "The Spoon", Nicole is enraged when she finds out Richard sent Gumball and Darwin Convenience Store Gift Shopping. From the second season on, even Anais is allowed to stay home alone, while her older brothers regularly travel all over town, either through public transit or by foot. This overlaps with Characterization Marches On, as both Darwin and Gumball were a lot more childish in the first season, despite neither of them aging since.
Steve started out as a snarker with a heavy dose of attitude instead of an adorkableButt-Monkey. For example, in "With Friends Like Steve's" he pretends to be excited about spending the day with his dad and then deadpans that he'd rather die, something that would just come across as cruel for Steve of the later seasons.
Roger frequently complained of being unable to leave the house. In later seasons it's established that Roger's had multiple disguised personae for decades.
The show's political humor was much more blatant in the first seasons, with most of Stan's abrasive behavior provoked by his Right Wing extremism (similarly Hayley was more a hypocritical Left Wing extremist). A lot of this had to do with America's political context at the time; the first episode aired in 2005, just after George W. Bush's re-election, a time when attitudes on the war on terror and opinions on counter-terror espionage tactics were big partisan cleavages. As time passed the show evolved into a more traditional (if still over the top) family sitcom, with Stan acting more as a traditional Bumbling DadUnsympathetic Comedy Protagonist.
The pilot episode relied heavily on Family Guy's trademarked cutaway humor, which would fortunately be dropped very quickly. Also, Stan was much more overt in his paranoia towards Hayley, such as subjecting her to a full body pat-down when she enters the house, and Roger's "clockwork" discharge of protoplasm was rarely mentioned again.
Toshi's mom looks very different in an early episode than she would later on. His sister Akiko was first shown as being much younger than him, but was later redesigned to be around the same age.
Animaniacs had surprisingly little of this compared to other cartoons, but still some oddities here and there:
In the earliest episodes, Yakko, Wakko and Dot were often referred to collectively as "the Warner brothers" by other characters, instead of the more familiar and Dot-inclusive "the Warners" or "the Warner brothers and their sister Dot."
Skippy Squirrel's first few appearances portray him as a Genre Blind wide-eyed innocent, seemingly about six years old, as opposed to the competent, Genre Savvy, seemingly ten- or twelve-year-old sidekick to Slappy that he usually is in later episodes. He also seems just to visit Slappy instead of living with her.
Archer: Early episodes implied that ISIS was a very large organization, with Malory making an offhand reference to fifty other agents who wanted Archer's job in the pilot. In later episodes, it's just the main characters and occasionally a few people with desk jobs; when the team needs a replacement agent, Malory starts looking at Cyril rather than just bringing in someone new.
In the early episodes, it's somewhat startling to see Cheryl acting like a normal-ish person, if slightly browbeaten by Archer. She doesn't start acting too crazy until Conway shows up, and even then it's pretty tame compared to what would come later.
For the first half of the first season, Krieger is a non-speaking background character, while Ray doesn't appear at all. It takes until Season 2 for the show to settle on its eight main characters.
For example Francine was more of a Jerkass instead of her more mellow Jerk with a Heart of Gold personality from later episodes, Sue Ellen appears several times despite having transferred to the school in third grade, Francine celebrated Christmas despite later being shown to be Jewish and celebrating Hanukkah, etc.
Even Binky Barnes being a legitimately feared school bully instead of a close friend of the gang seems weird given how long it's been, although this is 100% a case of intentional Character Development as he becomes more sensitive, gets into music and ballet, and gradually teaches the other Tough Customers to follow suit.
Due to a possible coloring error, nearly all the characters in the first season had white or extremely pale tongues. Muffy was also depicted with buck teeth like her book counterpart, but this was dropped quite quickly.
Interestingly, the characters were also shown to have rather exaggerated reactions when they got surprised or shocked, with some very fluid animation to match. This was toned down after the first two seasons, as the creators felt these were too cartoony.
D.W.'s friend Emily originally had very short hair and dressed in pink for the first few seasons before her design was altered to having shoulder-length hair and a blue dress.
Francine's cat Nemo had a much different design in his debut episode. As well as this, he was also named "Mimo" note a name Francine came up with on the spot to avoid using the cutesy wootsy name of Rose-Petal that her sister Catherine wanted to call the cat and didn't really have much of a personality until the episode "The Secret Life of Dogs and Babies", where he is depicted as a Jerkass with a touch of Deadpan Snarker when interacting with Pal and Kate.
As Told by Ginger Although it's more of What Could Have Been than this, the pilot was nothing but weirdness. Ginger has what only can be described as a pointy afro, her voice was slightly different, and her journal was pink rather than the cyan color that series adapted to afterwards. And it doesn't even end with the titular character. Dodie's pigtails started low on her head and arched up (and were very expressive), the whole main group of friends was treated as actual losers rather than the Cool Losers they'd become. Courtney had an entirely different design, Blake looked completely different and acted wild, Darren's headgear gave an annoying squeak whenever he spoke, and, the icing on the cake, both Darren and Miranda were white. The intro also has Courtney intentionally splashing Ginger with her car, while in the actual series she avoids the usual Rich Bitch stereotypes, and actually likes Ginger, though a little too much.
For a while, Appa was called a "Flying Bison" instead of the more prevalent "Sky Bison" that he became later.
In the earliest episodes, the fauna of the Avatar world was very alien and ran on Call a Smeerp a "Rabbit" (to wit, the above-mentioned Sky Bison). Eventually these creatures were replaced by a world full of more organic-looking Mix-and-Match Critters, leaving creatures such as the Sky Bison as The Artifact, as the species from earlier episodes couldn't just disappear.
The plot of "The Waterbending Scroll" is kicked off by Katara feeling jealous that Aang mastered several waterbending techniques much faster than she did, implying he's more adept at it or at least learns quicker. But later in the series when they're trained by Master Pakku, the exact opposite happens, with Katara becoming a master within only a couple episodes while Aang struggles and requires tutoring from her for the rest of the series, making this episode look rather strange in hindsight. Justified in a Technician Vs Performer sense with Aang as the latter and Katara as the former, averting Hard Work Hardly Works by surpassing him when he only trained when it was necessary, otherwise he was just goofing off in the snow.
The Avengers: Earth's Mightiest Heroes! has no Cold Opens in the first five episodes produced. The first season also has a number of cosmetic differences for the crimefighters, compared to the second season. Iron Man's mask has an opening for his mouth. Thor has a sleeveless and more colorful costume. Nick Fury has black and grey hair and no beard, like in the mainstream Marvel comics. It should be noted, though, that even after Iron Man and Thor changed their costumes, Marvel continued to use the old ones in publicity materials. If a viewer started watching during season 2, he or she might find it jarring to go back to season 1 and find no Previously On segments, a Thematic Theme Tune, and not a lot of guest spots by crimefighters associated with neither the Avengers nor S.H.I.E.L.D.
Early episodes of Batman: The Animated Series were more like a typical kids action show and not nearly as dark as the show would famously get, with plots like Batman ending up in a kid's basement and a more cartoony design for Scarecrow. It wasn't until the show started experimenting more partway into the first season that it settled into its trademark style.
Alfred fell victim to this in the first six or so episodes, with Clive Revill giving him a much stuffier and less warm characterization.
On the first two episodes, the transformations are treated with much more gravitas. With each member shouting his name and transformation code out loud, and being seen to transform by themselves. This is not limited to just the first transformation either, as almost all of them in the first two episodes are this way. Similarly, a big case is made out of Optimus' inexperience at commanding. This is never referred to again once the two parter is over.
Beavis And Butthead was almost a completely different show for the first two seasons. In addition to having even moreprimitive animation and artwork (the squishy cel physics and washed-out crayon style backgrounds) and voice acting (The two speak with Totally RadicalSurfer Dude accents, sound closer to Judge's regular speaking voice, and Judge also voices nearly all the female characters), the series itself was initially about two stereotypical metalhead teenagers who were not very bright (as opposed to the Too Dumb to Live they later became), and focused on the duo's destructive antics and pranks with little consequence rather than outright mock their stupidity. Even by today's standards it's clear why the Moral Guardians were horrified at this show when watching the earlier episodes. And the music video portions of the first couple seasons are noticeably more minimalist than they would be later on. The original approach was akin to recreating what two dumb kids would say while watching a video in real-time, basically stock reactions to random sights and sounds. Later on, said segments would evolve into the more structured joke setups that would be considered among the series' highlights. Lastly, Butt-Head's attitude towards Beavis was also originally less casually-malicious - it's somewhat shocking to re-watch those early episodes and hear him say "Huh huh, you're pretty cool, Beavis!"
In early episodes of Ben 10: Omniverse, Khyber whistles with his lips instead of his neck-holes, Rook used contractions (despite the fact that in later episodes, it's shown Rook's people consider contractions akin to swearing and anytime he uses one it's an Out-of-Character Alert. But, he is still formal), and Pakmar isn't a Third-Person Person.
The first two episodes have slightly more in common with the two previous series, albeit lighter, is paced somewhat differently than most later episodes, and even seems slightly more moderated in its silliness. This likely has to do with the fact that the script was penned by the late Dwayne McDuffie.
In Biker Mice from Mars, several aspects of the first episode "Rock and Ride" become rather odd in regards to the show's later episodes.
Throttle states that most of the Martian mice were wiped out. While he doesn't go into detail, his statement seems to imply that he, Vinnie, and Modo are the sole survivors of their race, which is contradicted by the subsequent appearances of other Martian mice like Throttle's girlfriend Carbine and Modo's nephew Rimfire.
Dr. Karbunkle is said to be responsible for Modo losing his arm, but it is suggested that Modo got his robotic prosthetic himself. This is eventually contradicted in a flashback shown in "Verminator" and the three-part episode "Once Upon a Time on Mars", where it is shown that Karbunkle actually made Modo's robotic arm himself.
Greasepit's voice sounds more gruff and less dim-witted than it does in later episodes.
Throttle, Vinnie, and Modo are shown flying in space with no apparent concern over the survival of their planet, when later episodes make it clear that in addition to stopping the Plutarkians from destroying Earth, they also wish to undo the destruction Mars suffered at the hands of the Plutarkians.
The early episodes showed the possibility of the series being another Dark Comedy adult animated sitcom, with shades of comedy similar to Family Guy, Bob was a bit more of a jerk, the kids were a bit more willing to bully each other and there were jokes like Louise naming the burger of the day "The Child Molester". Later on, the focus shifts to the family's quirky but loving ways towards each other, taking a much more lighter comedy and more heartwarming episodes.
"Human Flesh" paints Hugo in a sympathetic light, showing that while he was acting petty, he was also suffering, even coming around in the end and getting Bob his restaurant back. Later episodes completely forget this characterization, turning Hugo into a Hate Sink who extends his vendetta even to the object of his affection, Linda, in an attempt to get the Belchers out of business.
The Five-Episode Pilot of Chip 'n Dale Rescue Rangers for some reason actually portrayed villain Fat Cat in a way so that he acts like a human when no one's looking, but like a normal house cat when he is with humans. From the second episode onwards however, he is now always shown acting like a human. Justified since in the pilot he is owned by a criminal mastermind named Aldrin Klordane, and after Klordane is arrested Fat Cat operates on his own.
The first season of Code Lyoko definitely fits the bill. For a start, Aelita is trapped on Lyoko and isn't seen on Earth at all until the season finale (compare to later seasons where she lives on Earth full-time). Furthermore, season 1 is also very formulaic, the pacing is noticeably slower than in later seasons and at this point Sector 5 isn't know to exist. Couple that with the English version using different terminology than later seasons (sectors are called 'regions', Kankrelats are called 'Roachsters' etc.), and very different 3D graphics, and it almost feels like a totally different show!
Early on, Sector V was apparently the only KND unit in the world; it's not until the end of the first season that any others are mentioned and the second season that we actually see any. Their specialties and specific personalities besides Numbuh 1 being the official leader had also not been established yet, Numbuh 5 was almost The Voiceless, Numbuh 4 didn't have his famous crush on Numbuh 3, and the show itself was far more of a comedy (with downright bizarreGrossout Show-style plots relying on Rule of Funny) than the action/comedy it became as the series progressed. Also, some of the early gadgets didn't have the acronym gags.
There was very little continuity in the beginning, to the point you can watch most of the early episodes out-of-order.
The first episode title was "No P in the OOL" as a Pun instead using the Fun with Acronyms titles for which the series is famous.
In the earlier seasons, "normal" prisons clearly existed—Count Spankulot is seen in one in at least two episodes (S.P.A.N.K. note where the adults don't proveuseless for a change and the local court is actually seen sentencing him!) and L.O.C.K.D.O.W.N.). Later on, all of the KND villains were locked up at a special facility in Antarctica.
Teenagers were implied to be neutral instead of working on the adult's side the first episode they were mentioned in.
The KND were heavily implied to be Villain Protagonists, albeit sympathetic ones, usually harassing authority figures for petty reasons more akin to realistic rebellious kids, and coming off as rather incompetent (eg. one episode has them try to crash a swimming pool during adult swim, another has them try to destroy a supply of pianos just for how annoying they are; they fail miserably in both). Later episodes made them more unambiguously heroic, opposing adult villains with clear malicious intention.
The third-season episode of Count Duckula "Unreal Estate" was in fact an early pilot that was initially unintended to be aired outside to test audiences. As such, there are noticeable abnormalities, punctuated by it being aired so late in the show's run.
Von Goosewing notices in his newspaper that Duckula is back from the dead, seemingly starting off his vendetta against him.
Some of the animation looks very off-model and bizarre and more akin to the somewhat uglier character designs that were rejected prior to season 1. The title sequence animation of Duckula playing his harmonica originates from this episode.
Dmitri and Sviatoslav have their voices, but not names, the other way round.
Dan Vs.: While the show has lots of Black Comedy and all the main characters get away with a number of serious crimes on a regular basis, the show usually stops just short of having them actually murder anyone. Not so in the first episode, "New Mexico", where Dan and Elise get revenge on the state of New Mexico by hijacking a UFO and disintegrating random citizens of the state.
Daria's early gimmick was that whatever odd situation the title character had been placed in, she could get through it and upstage her peers and antagonists, at Lawndale High and home, by her wits and effective use of irony. Daria became more introspective in the later seasons.
The original Mickey Mouse was a far more mischievous character. As he become an iconic hero, parental pressure made him less mean-spirited and more of a Nice Guy. He also wore no gloves in his earliest cartoons. Those were given to him later to make sure that you still see his hands even if he held them across his black belly.
Donald Duck had a far longer beak and neck in his earliest cartoons.
Goofy's first incarnation was very weird. He actually looks older than he looks now, with a beard and glasses!
The second episode of the original Nickelodeon version of Doug, "Doug Can't Dance", was the original pilot interspersed with new footage. As a result, the episode constantly jumped between art styles and showcased Roger with a different gang of thugs as well. Doug also refers to his journal as his "diary"; later in the series, people calling it a "diary" became a source of annoyance for him.
Comparing the depictions of the older Dora characters in Dora's Explorer Girls to them in the Dora episode "Dora's Christmas Carol Adventure" shows several differences. Dora's tweenage design is slightly different in the Dora the Explorer episode, she never moved to an urban environment, and she's still presented as an adventurer. Backpack never got her Girliness Upgrade either and Boots is a Fully Dressed Cartoon Animal. Comparing the Explorer Girls special to the Dora And Friends: In The City series shows differences as well. Pablo didn't exist in the special, the art style was originally more similar to the original Dora series, and it wasn't done in the same faux-interactive style of the original series.
Early episodes had Foxxy Love being the most prominent housemate (as opposed to Captain Hero), as well as an antagonistic and unsympathetic Toot Braunstein. The pilot even had black and white blood for Toot, and she had a retraux vocal effect.
Foxxy and Princess Clara were both much more sympathetic in the first episode. Foxxy had a Hair-Trigger Temper and was violent but still wasn't the shifty schemer and overall Jerkass she'd eventually become, while Clara's politically incorrect opinions stemmed from being raised by her bigoted father rather than her being truly evil.
The first season had cruder animation due to a studio change. Many of the character designs and personalities were also altered slightly during the second season (the former is easily noticeable due to being used in the opening credits, which remain unaltered throughout the show's run). The pilot is noticeably darker (if still slapstick), Rufus and Amberley act more as the main protagonists with goofier personalities, with Urpgor (here only a minor character) and Sgt Blob's men actually getting shooed out in the second part, a stark contrast to their Villain Protagonist role afterwards.
While most of the series afterwards was a lite Villain Protagonist series, the earlier seasons were far less subtle about it. The heroes lacked even their occasional token side plots from later episodes, and in addition were far more hostile and sadistic in stopping in the Urpneys. Later episodes seemed to take more measures to ensure the heroes were at least moderately sympathetic and attached to the plot, and, in something as a subversion of the trope, started reverting more to their pilot characterizations. While most of Seasons One and Two were more simple, relaxed scenarios with the Urpneys just trying to sneak into the Land of Dreams, Seasons Three and Four utilized world travelling plots with Rufus and Amberley, allowing them to have new characters and realms involved in the feud.
The early episodes of Ed, Edd n Eddy had more grotesque animation (looking almost like Danny Antonucci's work on MTVnote specifically The Brothers Grunt, only scaled back). Double D was more mellow and less uptight, Ed was only slightly dense and spoke more coherently, and Eddy was more of a Loveable Rogue. In addition, while still luckless, the trio occasionally got the odd karmic victory every odd episode; they actually succeed in getting jawbreakers in the pilot (only to chase after them when they rolled away). There were also noticeable differences in dialogue and plot structure.
In the original first season, Timmy was the Only Sane Man, Cosmo and Wanda were a pair of cheerful wacky fairies ("two halves of a whole idiot"), Cosmo's voice was deeper and sounded more like a gameshow host (Word of God said he was supposed to sound like a used car salesman), and Vicky feared her parents.
In the original Oh Yeah! Cartoons shorts, the animation was a lot cruder and it seemed that Cosmo's and Wanda's current personalities were reversed: Cosmo being the more down to earth one and Wanda being the ditzy spouse, though neither really came across as dumb (contrast crazy and stupid). Jorgen was a regular Fairy Godparent (with a very scared godson) instead of being an authority figure of fairy world. And Timmy's parents were The Faceless.
Timmy was also voiced by Mary Kay Bergman in the original shorts. When the series was picked up, Timmy was voiced by Tara Strong due to Bergman's death. However, when the shorts were re-aired on television, Strong's voice was re-recorded over Timmy's lines.
In early seasons, Timmy losing his fairies didn't include having his memories erased. It wasn't until the Season 3 episode "Origin of Denzel Crocker!" that this became an aspect of losing ones fairies.
Vicky mentioned having a little brother in the first "Oh Yeah! Cartoons'' short however he was subsequently replaced with a little sister, Tootie.
In the first season episode "Father Time," Timmy uses the heat vision he wished for earlier to win a race. The second season would introduce the "can't use magic to win a competition" rule.
The first few episodes are much different from the show as it's known today. The animation is much cruder, characters lack their distinctive voices (Meg even has a completely different voice actress for the first 10 or so episodes), and many of them lack their more notable character traits (Meg isn't the Butt-Monkey and is in fact something of a bratty Daddy's Girl who is embarrassed by her parents and actually has friends, even if they are average-to-geeky girls just like her), Peter lacks his Jerkass qualities and is a more conventional well-meaning Bumbling Dad, Brian is the Only Sane Man who drinks martinis a lot and lacks his overly leftist traits that became prominent later on, and Stewie is a more malicious Evil Genius type who actively tries to murder Lois on several occasions). Notably, the setup is far more whimsical and tongue in cheek, more a light-hearted CrapSaccharine universe, with the Mood Whiplash of later seasons far less evident. A lot of non-flashback gags also resemble those that The Simpsons is known for, which is why a lot of critics compared Family Guy to The Simpsons when it premiered.
A lot of the characters had noticeable "thin-line" eyebrows in the first two seasons, which disappeared completely by the third season, sans Stewie.
Chris originally wore earrings, which came from one of his earlier designs as a punk rocker, which also vanished after two seasons.
The episode "Peterotica" parodies the case of The Simpsons when Peter recalls the show starting out as sketches on The Tracey Ullman Show. During this Cutaway Gag, the art is more unrefined, the animation is more expressive, and the voices lack refinement (especially Stewie, who has a cockney accent).
Bill Cosby had produced a "Fat Albert" cartoon special before the Saturday morning show that was a world away from the series - character design was realistic with a lot of sketchy line shading, animation was more sophisticated, and the backgrounds were real-life filmed cityscapes.
Other than the cartoon gags and art style, one would be surprised to know that Feline Follies is the beginning of the Felix the Cat series. Felix is named Master Tom in the cartoon, and wouldn't get his definitive name until two shorts later in Adventures of Felix. He looks and walks like a normal housecat instead of a Funny Animal, and his womanizing persona is nothing like his jovial, altruistic personality from later cartoons. And Felix wasn't part of his own standalone series here—it was actually included with two other cartoons as part of the Paramount Screen Magazine program, which the cartoon was improvised for to fill in for a tardy animators work. There is no Magic Bag of Tricks (which would be introduced 40 years later in Joe Oriolo's made-for-TV series) or other major characters besides Kitty. And the ending has Felix killing himself!
In general, the silent era cartoons have virtually nothing in common with the more famous Felix introduced in the late 50's cartoons, which was an In-Name-Only adaptation of the character. Felix is the only major character most of the time, with the only recurring extras being Kitty Kat and Inky and Dinky, and even they show up sporadically—none of the TV era characters like Professor, Rock Bottom and Master Cylinder appear in the silent shorts. And the tone of the cartoons is much darker, with surrealistic gags and urban stories rather than the pure kids fantasy the series later turned into.
In his first appearance, Dino could speak. And not just fourth-wall breaking asides like the various animal-appliances. No, he carried on full-on conversations with the human characters. Which makes it all the stranger that the plot of his initial episode revolved around Fred and Barney hunting him for sport! In the end, they only let him live because he offers to do household chores for Fred. None of this is ever referenced in any later episodes, which portray him as a simple house pet.
Compared to later seasons, the first season had somewhat different character proportions, but what's really noticeable is the voices. In particular, Bender's speech is a bit more slurred, while the voices of Farnsworth and especially Hermes are markedly higher pitched. note The actors remain the same throughout the series; it's evident that they hadn't quite nailed the voices yet. Hermes' accent was also a bit vague and inconsistent until it was finally settled upon as Jamaican while Farnsworth delivered his catchphrase in a less over-the-top manner.
Most early episodes had a "the Planet Express crew visits another planet and gets into wacky hijinks" plot (eg: "Fear of a Bot Planet" and "My Three Suns"). Later episodes took place mostly on Earth and were more characterization-based.
Zoidberg was much less...Zoidberg in Season 1 than he would be in later seasons; jokes centered on him tended to focus primarily on his nonexistent grasp of human anatomy, rather than his status as the universe's chew toy. He was also drawn with human-like teeth.
In the first mini series (The MASS Device), Cobra Commander and Destro had a bickering but slightly more cooperative relationship. Cobra Commander still had the hissing voice but it was deeper and he wasn't the cartoonish butt monkey that he would later become. Additionally, not everyone was firing red or blue lasers, machine gun fire was heard and Rock and Roll was shown firing an M60 machine gun as opposed to the typical laser gun that all the Joes later carried.
The first two episodes of the unaired Garbage Pail Kids Cartoon. had the five protagonist Garbage Pail Kids depicted as normal kids who become deformed when they go on missions and Trash Can Ken serving as their Mr. Exposition. The rest of the series had the Kids permanently in their Garbage Pail forms and had no mention made of Trash Can Ken.
Despite what the Gainax Ending of "My Fair Mandy" suggests, early episodes of the show had Mandy smile with no consequences on reality. Of course, these smiles were usually of the malicious kind (she's also smiled in the Christmas special with no disaster, but that's another story).
In "Trepanation of the Skull and You", the original short film starring Billy and Mandy that creator Maxwell Atoms made in college, the two characters are far different from how they ended up in the series. Billy is at least somewhat less of an idiot, Mandy is much more cheerful and extremely different from her final design, and both of them are taller and thinner.
The first billed Heckle and Jeckle cartoon, "The Talking Magpies", was actually a Farmer Al Falfa cartoon. The magpies in question were a married couple whose quarreling over a nest disturbs Al Falfa and his dog (an early version of Dimwit). Heckle and Jeckle took their more familiar designs in the next cartoon, but their voices were not the Brooklyn-esque and British accent they were more noted for. Syd Raymond voiced them at the time, with Jeckle sounding more like Curly Howard.
The first season is a lot different from the other seasons. The animation is of much lower quality, with lots of Off-Model scenes, there were fewer episodes centered on Helga (and she lacked any redeeming qualities for a while, with the abuse and neglect she suffered being used as a straight-up Hilariously Abusive Childhood), Arnold has a crush on Ruth, who is nowhere to be found after season 1, there is a heavier focus on bizarre one-shot characters as opposed to Arnold’s classmates, and on top of all that, Arnold is FAR more child-like and immature compared to the later seasons.
The seven-minute pilot has, among other differences from the rest of the series, a noticeable absence of Ami and Yumi's manager Kaz.
The first season used more conventional Episode Title Cards, while seasons one and two would instead have brief live-action segments that featured a card depicting the episode's title lying around somewhere or being held by the real Ami or Yumi.
For its first season, Home Movies was animated using the infamous "Squgglevision" method, but switched to more traditional Flash animation from the second season onward. In a case of The Danza, Brendan's mother Paula was voiced for the first five episodes by a different actress — namely, comedienne and Squigglevision veteran Paula Poundstone. Also, fan-favorite character Coach McGuirk was a washed-up Jerkass rather than the laidback lovable loser he eventually became.
Invader Zim: In at least two early episodes we see Gaz smiling. The closest we get later on is a wide-eyed Jaw Drop at the GameSlave 2 commercial. She smiles while threatening Dib in the "Taster of Pork" episode, so clearly the creators were OK with an occasional smile. She also is far less violent and sadistic towards Dib in early episodes. In the first episode, she overdramatically declares that her brother "will pay!" for drinking the last soda, but acts perfectly calm when he enters the room a moment later, whereas in later episodes, she would beat him up numerous times for perceived slights.
The intro presents The Misfits in an unusual manner. Roxy is the one in the middle instead of Pizzazz, the Face of the Band and the lead singer. Also in the actual theme itself you can barely even hear Pizzazz, instead Stormer seems to be the main singer. Stormer herself looks meaner than usual though that could just be the animation quality, however we also know originally Stormer wasn't the Token Good Teammate at one point in development.
The series was originally mini-episodes before being expanded into a full series. These episodes are notoriously ugly and feature different designs for several characters. There are also some oddities, like how The Misfits and Eric attempt to outright murder The Holograms several times and how the there are almost no transitions between the dialogue and the songs.
In Season 1, Superman and Wonder Woman sported cheekbones, which made them look older than they were supposed to be. Realizing this, especially as Superman's design was criticized by fans for excessive lines, their designs were tweaked to remove the cheekbones.
Huntress initially sported a design that invoked the costume she started wearing in the comics during Batman: Hush. Starting with "Double Date", when she got a speaking part, she got a redesign that was more faithful to her Hush costume.
The first season of KaBlam! has some early installment weirdness to it compared to the rest of the series:
The Henry and June wraparounds had much cruder animation and character designs than the rest of the show. Henry also played the role of The Straight Man while June was The Ditz. As the show went on, Henry got a lot more narcissistic and became the show's punching bag (as well as taking a level in dumbass in the final season) while June got snarkier and a lot more intelligent, becoming the only sane girl by the end of the series. The wraparounds were also a lot more "zany" and off-the-wall (while it was always a pretty crazy show, season 1 was a lot denser and wackier).
The Sniz and Fondue shorts from season 1 were done by a different animation house (The Ink Tank instead of Funbag Animation Studios), were done in traditional ink and paint as oppressed to the digitally colored episodes in the second and third seasons, and used stock music cues from Associated Production Music (which Nickelodeon uses a lot for their shows, including several KaBlam! segments) along with the original music (season 2 ditched the APM cues for the short).
The Action League Now! shorts "Where Pigeons Dare" and "Sinkhole Of Doom" were closer to the original two shorts made for All That in its first season in both quality and writing. At times there was also a lot more stop-motion going on compared to later shorts (possibly to save time and money). The Action League themselves were also more competent than in later shorts (but not by much).
The Life With Loopy pilot "Goldfish Heaven" (which aired during the seventh episode of the show) had a lot of early installment weirdness. As the short was using earlier versions of the stop-motion puppets, a few of the characters received some changes. Loopy's hair beads were constructed as part of her head instead of separate, while Larry wore a different outfit, had a longer neck, and was able to move his head separately from his neck (which none of the puppets would be able to do for the rest of the series). He also had a different voice actor. The sets were also smaller and less detailed than later on.
The first few shorts for The Off-Beats didn't air on the show, but during commercial breaks on Nickelodeon from late 1995 until KaBlam premiered. In the original shorts, Repunzil's dress was purple instead of teal, and the very first short was entitled The Misfits (presumably this was changed as it shared a name with a real band).
The Pilot suffered from this tremendously: the animation is nowhere near that of the rest of the series, the character designs dangled around the Uncanny Valley, Kaeloo sounds like a grown man instead of a young female and Bad Kaeloo has a vocal sac. Also, StumpyWINS for once!
For the first episode, "Let's Play Prison-Ball", Stumpy refuses to be on Mr. Cat's team because Cats Are Mean. Episodes which come a little later in the series have him willingly team up with Mr. Cat to pull off some antagonistic deed, and he idolizes him.
In the second episode, "Let's Play Doctors and Nurses", Mr. Cat was the perfect example of Evil Is Hammy. In later episodes, he's one of the least hammy characters there is on the show.
In the first two seasons the series seemed more toned down and less comedic. Dr. Drakken was also a serious villain early on, and Shego was a mook who was only occasionally sarcastic. The art is also quite different in the first season.
Kim was originally weirdly hostile toward Rufus, calling him a naked freak among other things, and had something of an ego. Later episodes quickly made her much nicer, if somewhat less believable. Most of these changes can be attributed to the departure of the original director and producer, Chris Bailey, who allegedly clashed with co-creators Schooley and McCorkle on the show's creative direction. The second season had a number of rotating directors before Steve Loter was installed as the permanent director for the third season.
"Tick, Tick, Tick" had Steve Barkin with blond hair, and all future appearances had brown hair. Kim's hair dryer grapple gun was also purple instead of blue.
Ron had a deeper, more adult voice in early episodes.
It was originally a more traditional family sitcom. Just like most shows that run for 10-plus seasons, the characters started off as more muted and simplistic versions of themselves. But the overall tone of the show changed as well: Whereas early on, Hank (as well as his friends and Peggy to a lesser extent) served as the Only Sane Man in plots about the encroachment of progressivism into the good-ole-boy community of Arlen, later seasons tended to focus more on the main characters' shortcomings as a whole. Hank had to learn to change and adapt with the times, Peggy was confronted with her unrealistic image of herself (which does explain why her Spanish comprehension faltered in later episodes and why she became a Small Name, Big Ego), et cetera. Luanne was also somewhat smarter and had more of a spine in the earliest episodes, not to mention her voice was slightly deeper, in contrast to the naïve ditz with a higher-pitched voice that viewers knew her as for most of the show's run.
Two of the earlier episodes ("Keeping Up with Our Joneses" and "Hank's Unmentionable Problem") had segments during the closing credits where the characters address the audience (Boomhauer compares cigarette smoking's effects on lungs with a carburetor becoming dirty overtime in the former episode. The latter episode had Hank apologizing to viewers who may have been offended by the Toilet Humor and butt nudity shown in the episode, even though it actually had plot relevancenote the episode was about Hank trying to beat his constipation, so there were a lot of scenes of Hank on the toilet, people talking about bowel movements, and Hank had a colonoscopy, which does call for rear nudity). Later episodes either have a stinger scene in the end credits where the fourth wall isn't broken or no scene at all.
Early episodes had the titular pet shop as having a full staff, such as Raul, the groomer, albeit none were seen onscreen except Mrs. Twombly and Blythe. Several episodes in, however, all of them were quietly removed with no explanation, leaving just those two. In addition, pets were dropped off for reasons other than the day camp, such as the aforementioned grooming, but as the rest of the staff was removed out the series, people would drop off their pets solely for the day camp.
The first season is the only season that does not end with the second part of a two-part episode. Instead, the season ends with the first part ("Summertime Blues") and the second season opens with the second part ("Missing Blythe"). This two-parter is also the only one to not have a "(title) - Part 1" and "(same title) - Part 2" naming scheme, and the only one to not have a To Be Continued segment and a Previously On segment.
They were no different from the other cartoon series running at the time—mildly amusing musicals with bland characters, derivative of Disney's more polished Silly Symphonies (note the similarities in name), not to mention that the early cartoons were in black-and-white and drawn in a completely different style that actually looks more cartoony than the later shorts. It wasn't until Tex Avery was promoted to director that Looney Tunes began living up to the first part of their name.
Character designs were drastically different. Porky was much more fat and hung out with Beans the Cat. Petunia, Porky's girlfriend, appeared more frequently in the early shorts. Bugs and Daffy were shorter and less anthropomorphic. Bugs had a "screwball rabbit" character design. Daffy, instead of being sarcastic, was simply off his rocker, making frequent whooping noises. Tweety was far more sarcastic and less cute in his early appearances, acting like a Dirty Old Man.
Even after the Loonification of the cartoons, some still come off as incredibly weird. Bugs Bunny (or his prototype) in particular started off more like Daffy Duck wearing a rabbit suit. Watch "Hare-Um Scare-Um" sometime and see Bugs openly refer to himself as crazy, jump around chuckling to himself, and even sing a Daffy-esque song about how insane he is. The "Bugs Bunny" from this cartoon was later retconned into a separate character named Happy Rabbit.
In some of the early cartoons, Bugs actually loses sometimes!
Daffy was more of a Bugs Bunny-style comic protagonist. Only in later toons did Daffy become a Butt-Monkey who is eternally jealous of Bugs.
Tweety Bird was featherless in his debut cartoon. Warners executives then forced the animators to give him yellow feathers, because they thought the bird was "naked". When Sylvester and Tweety are first paired together in "Tweetie Pie", Sylvester is called "Thomas", and he doesn't talk.
Marvin the Martian had a less nasal voice in his debut cartoon. His voice sounds more like a bad impression of Droopy.
It took a few cartoons for the Pepe Le Pew series to gel - the first short (Odor-able Kitty from 1945) ended with his wife showing up, and he drops the French accent, addressing her in a meek, nervous Midwestern voice! "Odor of the Day" is a particularly glaring case, since Pepe isn't even romantic in it.
In the Mumfie's Quest episodes of Magic Adventures of Mumfie do not decide on which way to draw Bristle and use a squeaking noise for Mumfie's sneezes and falls rather than that noise which sounds like he farted.
While the premise of He-Man and the Masters of the Universe (1983) was pretty consistent throughout its run, the material that came out before the cartoon is another story. The earliest mini-comics depicted He-Man as a Barbarian Hero, the greatest warrior of an uncivilized jungle tribe, whose great strength comes from that harness he wears; there was no Prince Adam or "By the Power of Grayskull!", no Orko providing comic relief, etc. He didn't even use the Sword of Power, preferring the axe his toy also came with. When DC started making comics about the series, they added a lot of that material (except for Orko, who was created for the cartoon). However, DC's comics characterized Prince Adam as a womanizing party animal and troublemaker — a far cry from the Adam seen in the TV series. The dialogue in the DC comics was also archaic, almost Shakespearian (think Marvel Comics' Asgard prior to 2006 or so), whereas the cartoon and the comics that came after it featured modern English diction.
In the 1983 cartoon and related comics, Cringer/Battle Cat, Adam's pet tiger, could talk. He hasn't been depicted as speech-capable since the 2002 series, so anyone more familiar with more recent He-Man material is certain to find that a little hard to adjust to.
Very early versions of the comic held that Skeletor came from another world where he lived with "Others of his kind." While Skeletor's origin varies a bit between incarnations, all series afterwards almost universally agree that he's a native of Eternia.
Very early episodes depict Mega Man as having a weird Stay in the Kitchen attitude towards Roll, who was desperate to get out in the field with him. After about two or three episodes this plot thread was quietly dropped.
Early episodes also had Eddie as a somewhat important supporting character. He was increasingly phased out from then on, to the point that he only appears once in season 2.
The unaired pilot also had animation and designs that were much more accurate to the trademark art style of the Mega Man games. The show proper has a more Americanized style to it.
Mike, Lu & Og: The pilot short from What A Cartoon! Show is very different from the series proper. Citing a few examples, Lu and Og are a little more naked (Lu's bra is not connected from the back and Og only has one loincloth in front, exposing his rear) and the animation was a more choppy and simple (while Pilot Studio in Russia was always involved with the show, the pilot (along with "The Good Ship Bad", "Jujubombs" and "High Camp") was actually animated there, whereas the show itself was animated by Nic & Sae Hahn Productions in Korea).
The first Mr. Magoo cartoons were different from his later appearances. While he was still nearsighted, Magoo had a slightly more detailed appearance and had the qualities of a Grumpy Old Man (In fact, his debut short The Ragtime Bear ended with him trying to shoot Waldo!). His later cartoons dropped those qualities and made him the happy-go-lucky, lovable geezer we know and love.
The premiere made the series look more like a Magical Girl show. However, the characters' status as the Elements of Harmony generally go unacknowledged outside of two-parters, with the show's structure mainly consisting of Slice of Life episodes.
Spike is less competent in the pilot and some early episodes, not even knowing how to spell words like "brink". Twilight also treats him rather harshly, and is more an acerbic Jerk with a Heart of Gold in this and certain early episodes, compared to the Super OCDAll-Loving Hero she usually is season 2 onwards (though that can be chalked up to character development).
It took a while for the visual effects of unicorn magic to be standardized, and even then, the Color-Coded Wizardry didn't really show up until "Lesson Zero" in season two.
"Swarm of the Century" is the only episode in the entire series to have a scene with completely legible English-language writing, when townsponies make a banner that reads "Welcome Princess Celest" (The townsponies state that they couldn't fit "Celestia" on their welcome banner). All other visually depicted instances of the printed or written word are made with chicken-scratch, made-up written lettering, or mashed-together letters with filled-in areas that look somewhat like Latin letters and real-life words.
The third episode of the series, "The Ticket Master", was the first episode to be written, and it shows - Spike has lacks his crush on Rarity, non-unicorn ponies can somehow levitate the tickets above their heads, the episode opens with Twilight helping Applejack with the harvest, which clashes with the latter's convictions in "Applebuck Season", etc. It's also the lightest episode plot-wise, as it was originally intended for a Two Shorts format.
"Applebuck Season" openes with Big Macintosh having his first speaking lines and manages to say two complete sentences! Which is a rarity in the series as most future episodes will only have him saying "Yup" and/or "Nope" whenever he appeared and maybe a two or three word sentence if you're lucky, barring the occasional episode that gives him A Day in the Limelight where he is a little more talkative.
In general, the first season is a lot more Slice of Life than any of the later ones, which tend to have more adventure-type episodes that include premieres/finales that bookend an overarching theme or plot. The season one finale, "The Best Night Ever", is just a standard slice-of-life episode.
At the end of the series premiere, Princess Luna is shown to have a short, periwinkle-colored mane, in sharp contrast to her long and dark blue mane shown in later episodes. Fans wrote this off as being her mane style from before she was imprisoned in the moon, but the Season 4 premiere Jossed this.
In the pilot, the narrator refers to Celestia and Luna as "unicorns". Season 3 canonizes the fanon term "alicorn" for ponies with both wings and horns.
Despite Word of God to the contrary, some Season 1 episodes depict unicorns and pegasi as having physical strength on par with Earth ponies. For example, the three types of ponies seem evenly matched in the Running of the Leaves, and they all are able to dig through earth at the same pace.
The show's treatment of musical numbers likewise changes. In the first few episodes, any singing is done by Pinkie Pie - with the characters being annoyed with it. Starting with "Winter Wrap Up" midway through the first season, everyone else started singing their own numbers too. It can seem odd to see the other ponies rolling their eyes at Pinkie's singing in the two part premiere, especially when they all get their own songs as the show goes on. However, most songs are metaphorical, not literal.
The 1st season was the only one to have a recap of the lesson in just about every episode, through Twilight writing Princess Celestia a letter. Once the E/I requirement was lifted in season 2, these were gradually phased out, with "Lesson Zero" having Celestia tell Twilight not to worry about sending her a letter every week.
The end credits in the first couple of episodes were written in a fancy script font rather than the plain Helvetica Bold in later episodes.
The first two Multi-Part Episodes (the pilot and season 2's "The Return of Harmony") had their second halves aired at least a week apart, while every subsequent one premiered as hour-long specials.
In the very early episodes, ponies treated other fully sentient creatures like animals. (Cows were kept in barns and a stampeding herd of them had to be rounded up, and when the mane six went up against a dragon, they valued Fluttershy for being good with animals.) It wasn't until "Over a Barrel" that other sentient creatures were considered to be of other races.
Rather than being lost in the woods and trying to find their way home, Wirt and Greg are on a quest to find the titular Tome of the Unknown.
In the series, a major part of Wirt's Character Development is seeing Greg as something other than an annoyance and to stop treating him so callously. Here their relationship seems much better from the start, with Wirt even finding some of Greg's antics funny.
The Beast and the Woodsman, both important characters in Over the Garden Wall, are not seen nor mentioned.
The show only has narration at the beginning and end, but here it's spread all throughout the episode.
The first Phineas and Ferb episode, "Rollercoaster", lacks many of the show's mainstays and in general is very different from the episodes to follow it. A lot of these differences are lampshaded when the episode was given a musical remake, which involved the characters doing an In-Universe recreation of the events;
Dr. Doofenshmirtz's Evil Plan is much grander in scope than his usual focus on "taking over the entire Tri-State Area" (he's trying to reverse the Earth's rotation), and the key device in his plan is not an "-inator".
Buford and Baljeet aren't present in the first few episodes, and even after they appear they don't become part of Phineas and Ferb's gang until a little later. Buford's first appearance in "Raging Bully" also has him purely as an antagonist, with no sign of him and Baljeet being Vitriolic Best Buds.
In the first Popeye short, Olive Oil's voice sounded nothing like her more cartoonish, signature voice.
The pilot to the 1980's Pound Puppies cartoon has some noticeable differences from the actual series.
Aside from his trademark howling, Howler does not speak, when the series has him Suddenly Voiced. He also doesn't wear a vest.
Bright Eyes appears to be older in the pilot than she was in the series.
Nose Marie is instead named "The Nose".
The pound is run by a man named Mr. Bigelow instead of a girl named Holly. He is also Catgut's owner instead of Katrina Stoneheart.
Catgut himself had a more cartoonish and blob-like design.
Craig McCracken's first The Powerpuff Girls short (created under the title Whoopass Stew) features the Amoeba Boys as genuinely competent criminals. Also, the girls have no individual personalities, and defeat the Amoeba Boys by flying them to extremely close contact with the sun, causing them to melt. Also, Professor Utonium for some reason looked like Dexter.
Recess Season 1 was very different from the rest of the show:
The show was more fast-paced, exaggerated, and cartoonish, T.J. was more sarcastic and a borderline Canon Suenote (Plus, he was also drawn with highlights in his eyes, which only lasted the season), Vince was more of a Sour Supporter, Miss Finster and Principal Prickly were more sadistic (Miss Finster especially in "The Box"), Miss Grotke was less sympathetic and appeared less often, King Bob was more of an antagonist, the animation was more off-model, and Lawson didn't appear at all.
In some of the early episodes, such as "The Break-In", "The Great Jungle Gym Standoff", "To Finster with Love", and "My Fair Gretchen", Miss Finster doesn't sound as sinister as she usually does in the show.
The very first episode did not feature Gus, who transferred to the school in the next episode.
In the original pilot version of the first episode, "The Break-In", T.J. and the gang (barring Mikey) had very different character designs. For example, here's T.J.◊, and here's the rest of the gang◊. TJ had the same voice actor, though.
Seasons 1 and 2 were mainly centered on Mordecai and Rigby, usually about their job. Starting with season 3, the others characters get more focus.
The characters' personality were different. Mordecai and Rigby were more immature and would regularly slack off, Benson was an unsympathetic Mean Boss who regularly abused his authority and threatened to fire Mordecai and Rigby over petty reasons, Pops was even more of a Cloudcuckoolander, and Skips was only used for assistance. Also, Margaret was used as a love interest for Mordecai (mainly in the first four seasons) and in her earlier appearances, she would usually gets a new boyfriend, much to Mordecai's disappointment. Eileen, meanwhile, was a very minor character lacking sclera.
Muscle Man wasn't a main character in season 1. He was often limited to small roles, but until season 2 he started getting more involved with the plots. Also, Hi Five Ghost was the The Quiet One, almost not speaking at all and it was because he was jinxed.
The animation and art were also noticeably different. It's easy to watch both the pilot and its updated version "First Day" to notice this. Including the earlier seasons, the animation flows better than it does in the later seasons, and the art style started to get less cartoony as it goes on.
The first episode of Rick and Morty featured the main characters in a more negative way than in later episodes. Rick acted more like a neglectful and criminally insane sociopath rather than a Jerk with a Heart of Gold, Summer was a one-dimensional and spoiled brat, Jerry was obsessed with actively comitting Rick to a retirement home and Morty was said to have a mental limitation which never was brought up again. Their behavior changed either because of character development, or because the writers came to the conclusion that it wouldn't work as a constantly recurring plot formula. The Reset Button would often get hit a lot in that same season. Once the 2nd season rolled around, continuity began to creep in.
Rick originally had extremely pale skin in the first few episodes rather than the greyish-tinted skin tone he has today.
In the first season of Rocko's Modern Life not only was the theme song different, but Rocko was more paranoid and easily angered, Filburt was not a regular character, but when he did show up he was nerdier than in later seasons, Bev Bighead in all her season 1 appearances was more flirtatious and liked to party, and the style was cruder, and there was more gross out humor and innuendo than later on, and most plotlines involved Rocko trying to make it through everyday situations gone wrong more than in later seasons.
The first several episode of have a laugh track, along with severely low-key narration by William Conrad and Off-Model animation, which got better as the show went on since they outsourced to a Mexican animation studio which had been set up expressly for the show.
In the first few episodes, Boris had red eyes.
Some of the early episodes ended with only one title for the next episode, rather than two.
The first two episodes of Peabody's Improbable History had puns at the end.
Rugrats: While the "classic" episodes that most people think back on were about the friendship of the whole gang, who are all well-developed characters, working together to deal with various issues, fears, superstitions, things the adults are doing, etc, the first season is a way starker show about a largely-silent Tommy (and occasionally some of the other kids) being brought to some new location wandering off from his parents and accidentally getting into all sorts of trouble without them noticing, only to return to them unharmed at the end of the each episode.
The art style was also quite a bit cruder in the first season, and Tommy spoke with more of a grunt.
The pilot episode, "Tommy Pickles and the Great White Thing", was even stranger, with more bizarre animation that looks like Don Bluth on LSD, adult characters having long necks, and a different voice actress for Tommy.
During the first season (and in S2's "Chuckie vs. The Potty"), Chuckie is said to have a living mother and she actually briefly appears in one episode (with a completely different design). He isn't revealed to be a single parent child until Chaz becomes a more prominent character midway through season 2 (unless Chuckie's mother died around that time, and Chaz didn't feel the need to mention it until the Mother's Day special).
Chuckie was also a bit more of a Jerkass in the first season, often angrily complaining and yelling at everybody when things didn't go his way. He wouldn't become the disagreeable yet lovable sidekick we all know and love until the second season.
Funnily, it also seems like the characters experienced a little developmental regression after the first season. In season 1, they're able to successfully count to three and articulate fairly sophisticated words (even if they mispronounce them). Neither of which they would be able to do again from S2 onwards.
In the first season it was implied Tommy could speak a little, as there was the occasional episode where he didn't speak as he normally did and was mainly around adults at the time. The second movie establishes Chuckie as the first baby to speak.
A few early episodes seem to suggest that Reptar is a cartoon character in the Rugrats universe, and that he's capable of speaking. "Reptar on Ice" features a costumed actor singing his lines in a Reptar musical, "Toy Palace" features an animatronic Reptar toy that repeatedly bellows "Halt! I am Reptar!" when Tommy presses a button, and "Reptar's Revenge" features another costumed Reptar actor who openly talks to children while in costume. Later episodes, however, would more clearly establish Reptar as a parody of Godzilla who can do nothing more than roar, and primarily stars in live-action movies imported from Japan.
In the first few episodes Tommy wore a red shirt instead of a blue one and sometimes wore overalls.
Gross-out slapstick wasn't the only oddity that the early episodes suffered from. The animation is quite different compare to later episodes of the series, with more cartoon-ish movements and differently drawn characters. Hector's voice was very high-pitched in some of his earliest appearances (Most likley to make him sound more like a kid), Sanjay's skin was more yellow-ish, Vijay talked a little faster, Craig's voice is more nasally and louder, Tufflip's voice was deeper, the Dicksons' house had a completely different interior, and Chicken Chuck was only a background character who had very little involvement in the storylines. The pacing was pretty slow and some of the jokes can be pretty forgettable compared to Seasons 2 and 3.
Occasionally, they would make a few jabs at Season 1's gross-out slapstick in a few Season 2 and 3 episodes like "2 Tuff 2 Watch" and "Songjay".
The off model designs of the Simpsons for the shorts. They were poorly drawn animations of facial caricatures and were gradually swapped for the current designs. They were brought back on occasion to show how far they've come, such as in the last segment of "Treehouse of Horror XXV".
First were the Tracey Ullman shorts (which focused on the Simpsons family and had Lisa as being just as devious as Bart). Then come the first season or so, most of which is very different in tone and humor style to everything that came after it. In general most episodes are rather straightforward antics consisting of one storyline (contrary to later episodes where usually two or three story arcs are combined), usually revolving around Bart and/or Lisa. The pacing is slow, most of the characters haven't been properly established yet (or don't exist), and the jokes nowadays come off as awkward or too subtle to be funny. The animation is very amateurish, sometimes downright ugly to look at. Even though the show was still more realistic and less cartoony than later episodes, there are still occasional moments where the animation is more typical of a standard cartoon: weird expressions, super quick movements and rather kid-friendly silly voice acting. The social satire is there, but more subtle than in later seasons.
In particular, there's the episode "There's No Disgrace Like Home" (in which Marge embarrasses the family by getting drunk in public and Homer is actually ashamed of his family being dysfunctional. Later episodes, like "El Viaje Misterioso de Nuestro Jomer"note "The Mysterious Voyage of Our Homer," the season eight episode with Johnny Cash as the Space Coyote who advises Homer to find his soulmate would have it the other way around). The writers' commentary cheerfully admits that pretty much everything in the episode is "wrong" compared to later seasons (except for the personalities of Bart and the ancillary/supporting characters, like Moe, Officers Eddie and Lou, and Dr. Marvin Monroe), though that still doesn't stop it from having a scene that continues to be extremely popular (the climax where The Simpsons give each other electro-shock therapy and cause rolling blackouts all over the city).
Also notable is the completely different, more gruff voice Dan Castellaneta uses for Homer during the shorts and first part of the first season. The original voice of Homer was based rather closely on Walter Matthau. As well, after the first three or four seasons (after the initial craze died down, but the show still had good ratings to keep it afloat) the writers realized that Homer was a much better character for generating plots instead of Bart, as long as they kept him fairly unpredictable and dumb. Dan Castellaneta actually says on several commentaries that he never really made a decision to change the voice; he just kept trying his best to match the voice he used in the previous episode, and it slowly changed to one that fit the writing better.
There's also the early Off-Model appearances of an Ambiguously Brown-skinned Smithers with blue hair on the season 1 episode "Homer's Odyssey" (which was said to be due to an inking error), Lou the cop (whose skin switched from being black to being yellow due to the show's notoriously bad animation back in the 1990s), Barney the drunk whose hair matched his yellow skin, Miss Hoover (Lisa's teacher), who had blue hair instead of brownish gray, and Hans Moleman (whom the ink and paint people keep switching from brown to yellow — sometimes in the same episode).
The character of Troy McClure is voiced by Castellaneta in his first couple of appearances, before he was given to Phil Hartman.
Homer is not nearly so dumb in the earlier episodes, though he does mix up his facts (when he told Bart that Albert Einstein turned himself all different colors when he invented the light bulb) and does initially come off as clueless to his wife's and children's emotional problems. He is also not as much the Breakout Character as he would become in later seasons.
Ned Flanders wasn't the "everything-is-religious" extremist we imagine him being today in the very first episode, "Simpsons Roasting On an Open Fire." Of course he and his family are shown celebrating Christmas, but all their decorations are of secular Christmas characters (like Santa Claus and Rudolph the Red-Nosed Reindeer). In the early episodes, Flanders was just a nice, church-going man who had a beautiful wife and well-behaved children (which made Homer jealous of him). Then came the, well,Flanderization of Flanders and the rest is history.
In his debut episode, "Bart the General", Nelson Muntz is a genuinely sadistic bully who scares away everybody, and targets Bart especially. In subsequent episodes, he became far more well-known for his mockery of other characters' misfortunes with his iconic laughter ("Ha-ha!") and for being a dim-witted, mean-spirited delinquent with a soft side underneath. He also becomes of a friend of Bart's in later episodes (though their friendship is very inconsistent), with Milhouse van Houten and Martin Prince becoming his new bullying targets.
Mrs. Krabappel is much meaner in earlier episodes, her being more or less Bart's foil. She would become more three dimensional as a character later on (until she was dropped entirely due to Marcia Wallace's death).
In his very first appearance, Sideshow Bob is shown to be more or less happy working on Krusty the Clown's show, and you'd never guess he was harboring any of the resentment that would drive him to frame Krusty for armed robbery and embark on his career as a master criminal (though the episode, "Krusty Gets Busted" had something to do with Sideshow Bob's change in personality). And with the exception of one really brief scene Sideshow Bob's hair looks completely different than it normally does, instead looking closer to Krusty's replacement sidekick, Sideshow Mel.
Krusty himself often seemed more genuinely childlike and hyperactive in early episodes ("Itchy and Scratchy and Marge" shows him having trouble not playing to the kids when trying to have a more serious discussion on air), compared to the acerbic, money hungry Nice Character, Mean Actor he is in most modern episodes. In "Krusty Gets Busted" and "Like Father, Like Clown" Krusty is shown having flesh colored skin underneath his makeup, whereas in later seasons Krusty's pale face and red nose are a medical condition resulting from chain smoking and Krusty has to wear makeup to look normal.
During the first three seasons, Chief Wiggum was actually a very serious, no-nonsense cop who didn't like it when people didn't take the law seriously. Season 4 changed all of this and made him the corrupt, dim-witted bungler we know today. Similarly, his son Ralph Wiggum was a fairly normal kid in his first couple of appearances, but sometime in season 4 was when he became the incredibly stupid Cloud Cuckoolander we know and love today.
The Treehouse of Horror specials are slightly different in the first few seasons. The first four of them have Wrap Around Segments as ways of setting up the stories (II for example has them all happening as nightmares of Homer, Bart and Lisa). They were also initially opened with a segment of Marge warning viewers about the scariness of the episode. The spooky opening sequence also featured names of dead people (or ideals and institutions considered "dead," like television violence, American workmanship, and subtle political satire) on tombstones. These all were dropped due either to lack of time for them or writers struggling to come up with ideas for them. Additionally the first episode featuring Kang and Kodos the aliens has a third - Serak the Preparer who has not appeared since (Al Jean notes on the commentary that this is because "he costs money," being voiced by James Earl Jones).
In the first five seasons Itchy and Scratchy are more prominently featured on the show, almost appearing once in every episode when characters are watching TV. In later seasons they appear less and less frequently.
The first five or six seasons also regularly feature a couple of characters who would disappear altogether from the show because they just didn't click with the audience: The Happy Little Elves, Marvin Monroe, Bleeding Gums Murphy, Mrs. Glick,... Nevertheless they appear very prominently in the first two seasons. Radioactive Man would also count. He does appear in later episodes, but always in smaller and rare references.
Then there are character who make their debut in early seasons, but would only reoccur more frequently and prominently in later seasons, like Comic Book Guy, Cletus, Sideshow Mel, Database, Superintendent Chalmers,...
The opening theme was much different in the first season:
When Homer left work, an unknown man sat behind him eating a sandwich with tongs (changed to Mr. Burns and Smithers in the background).
Lisa's saxophone solo was originally an octave higher.
Bart skateboarded past a group of Springfieldians waiting for a bus. He picked up the bus stop sign and the bus sped by, the group forced to chase after it.
Lisa was given an extra scene where she arrived at the house first, followed by Homer who pulled into the driveway with Bart skateboarding off his car. Later seasons show Homer pulling in first, followed by Bart, then Lisa who cuts off Homer after he gets out of his car.
For those who came in after the 7th season, it can be weird to see early episodes where Lisa is eating meat along with the rest of her family. Early Lisa even seemed to have an affinity for fried shrimp. In one episode, she even bought a cow's heart from the local butcher in order to learn about heart surgery!
The episode titles for the first few seasons are more plain, including Bart the General, Krusty Gets Busted, Itchy & Scratchy & Marge, etc.
In early seasons, Lenny and Carl were more frequently seen at the nuclear plant than at Moe's Tavern. In fact, outside of "Flaming Moe's", they never actually appear at the Tavern. It isn't until Season 6 when they become regulars there.
Early on, Sideshow Bob and Sideshow Mel never spoke on "The Krusty the Klown Show", using slide whistles instead. This serves to inforce their roles as Krusty's sidekicks. Thus, it was a big deal when Sideshow Bob actually spoke when he took over the show after Krusty's arrest in "Krusty Gets Busted". This conceit was eventually dropped, and Sideshow Mel has been openly speaking since the third season of the show.
Season 1's "The Telltale Head" and Season 2's "Bart Gets Hit By a Car" both have the episode titles featured at the beginning of the episode during the opening credits, something that's never happened in any other episode.
The HD episodes of season 20 had the Simpsons' television replaced by a new flat screen TV in the intro, but whenever it appeared in the actual episodes, it was always the original CRT TV they've had for years. Even more oddly, the old TV made apparances in two Couch Gags. It wouldb't be until season 21 when the new TV would make actual appearances within the episodes.
"Heads or Tails", the pilot episode, is markedly different than the rest of the series. Sally sports her original comic's pink fur and black hair, NICOLE is a wheeled out desktop computer instead of a tricorder-type computer, Tails acts like a four-year-old (the age of his other cartoon counterpart at the time) instead of his eight-year-old self, and the SWATBots are shown with their comic-based gray coloring instead of their stealthy black coloring as well as a personality (two are shown laughing at Snively after an accident.) Rotor similarly has his undeveloped purple design used in the comics, with much more emphasis on his Adorkable qualities. To say nothing of how much Lighter and Softer the whole thing was: at the end a squadron of evil robots is repelled with water balloons.
The first season went through a few inconsistencies before season 2 set things in stone, especially since it was made by several writers rather than one, and the decision to have an arcing plot wasn't in place yet. Sally was more childish and arrogant, Snively was more genuinely loyal to Robotnik and actually thrived on his rare praise at points. Antoine's cowardice and pompousness was also more subtle. Some episodes such as "Sonic Boom" also caused continuity errors with the backstory established in the Second Season.
The show is essentially known as one of the modern era's leading voices in satire, but the first several seasons were much better known for being full of Vulgar Humor (not that it doesn't have it now; it's just that it used to be in excess, leading to a lot of complaints from censors and media watchdog groups), swearing, and plots driven on Rule of Funny. The lower budgets and actual-construction-paper animation also present a significant visual difference. Funnily enough, the newer seasons are far filthier and feature unbleeped swearing. The show itself lampoons all this when recreating the series' first scene with twice as much swearing and blockbuster computer effects in the Season 7 opener "Cancelled".
Cartman was also different in the show's early years, his personality depicted as the result of his mother's poor parenting and rarely exceeded a spoiled obnoxious bully (actually, his growth into more of a psychopath is one of the show's more realistic aspects). In addition the other boys often dished out as much as they took and acted more as childish Unsympathetic Comedy Protagonists with not much more clarity than the world around them.
South Park was also way smaller in the beginning. For example, Barbrady was the only police officer in town for the first six seasons (an actual plot point in "Chickenlover", where he retires and the town quickly falls in chaos) before Yates and other policemen were added in the seventh season. Barbrady then became the police chief.
In Terrance and Phillip's introductory episode "Death", their show is a cartoon in-universe and their cruder appearance than the other characters is because they're meant to be even worse-animated cartoons. This was later retconned to them being live-action comedians and all Canadians looking like that. A commentary even revealed that Trey Parker and Matt Stone had initially considered them to be British as well, before it was decided to make them Canadian. The Canadian retcon also led to Kyle's brother Ike being revealed as adopted, due to the split-head similarity (originally, all babies were to have that design. An Ethiopian baby can be seen appearing that way in "Starvin' Marvin"). Also, in their first appearance, Terrance was voiced by Trey Parker and Phillip by Matt Stone. All subsequent appearances reverse this.
In episodes 2 to 6 in the first season, Kyle was the one who says, "Oh my God, they killed Kenny!", rather than Stan. The seventh episode, the first Halloween Episode, had the line said by Stan as normal at the beginning, but the ending features a variant said by Kyle. Subsequent episodes have Stan as the primary deliverer of the line. On another note, "You bastards!" wasn't said in the Volcano episode.
The 1992 short "Jesus vs. Frosty", which came out before "The Spirit of Christmas", is even more drastic; the character that is to become Cartman is called Kenny and is The Voiceless, Future Kenny has no name and speaks coherently, and they both die. The characters are also missing their Garfield-styleSphere Eyes, having only unfilled circles and dots in their place.
In "Weight Gain 4000", Cartman wins an essay contest by cheating. In later seasons Kyle would be the one trying to move heaven and earth to prove it while no one believed him, but in this episode it's Stan among the four main boys who gets pissed. Later, he'd be the least likely to give half a shit.
Granted, the reasoning for this was that his girlfriend Wendy was upset about losing to him, which is more in character. When Cartman is exposed (and no one cares), Wendy is still indignant he gets no punishment, while Stan just shrugs it off.
The characters' voices were also different earlier on, even if some of them had the same voice actors (and keeping in mind that most of the child characters' voices were digitally tweaked). Cartman had a higher, raspier voice, while Stan and Kyle were somewhat higher-pitched. Cartman's voice began to gradually lose its rasp over the course of later seasons, while the pitch-shifting used for Stan and Kyle was relaxed somewhat.
The movie South Park: Bigger, Longer & Uncut also had much notable differences compared to how the show was for the last five years due to being created around the same time as the show's third season. If someone who was introduced to the later episodes of the show watched this film, they'd noticed the much cruder animation and jokes that were standard during those times. Also, certain characters who would rise to prominence much later on, most notably Butters and a few tertiary characters such as Craig and Token, are just background characters. Cartman himself is also the bratty jerk he was known for early on instead of the cunning and manipulative sociopath of the later seasons. Even Randy, the most notable adult character of the later seasons, is only given a single line in the entire film (questioning the V-chip).
The Unaired Pilot of "Cartman Gets an Anal Probe", the first episode of the series, has some drastic differences to the rest of the show. The most notable is that Cartman also has a father and a sister in his family, instead of only living with his single mother.
SpongeBob SquarePants Season 1 feels very different than the rest of the show, mainly due to being produced with actual ink and paint, rather than the ToonBoom software. Besides that, there's other stuffs in the first season this trope had came in effect, such as:
The voice acting was a lot more relaxed in this season than the rest of the voice. It's noticeable with SpongeBob and Patrick.
Sandy's tail is missing when she isn't in the treedome and she doesn't has the acorn on her suit (instead it's just three dots). Also, her introductory episode implies that SpongeBob may have a crush on her, but the writers didn't feel as if this fit well and this is mostly absent in later episodes aside from an occasional reference.
Patrick's eyebrows looks different in the first season (and a few early season 2 episodes).
The use of humorous time cards read aloud by the French Narrator is one of the show's most enduring Running Gags. Yet in the first season there were only two time cardsnote in the episodes ''I Was a Teenage Gary'' and ''SB 129'', the first example of which wasn't even accompanied by narration.
Kallus doesn't pay any particular heed to Zeb. This is despite the fact that Kallus participated in the genocide of Zeb's homeworld, and thus there are very few Lasat running around the galaxy.
Kallus, during the Cleansing of Lasan, acquired as a Battle Trophy a unique Lasat weapon called a bo-rifle from a Lasat Honour Guardsman he defeated in combat. He doesn't use it in "Spark of Rebellion", despite having since used it in all other combat situations he's been seen in. In fact, he can even be seen carrying it on his back in the scene before he boards the transport ship, making its omission even more puzzling.
Static Shock was originally intended to be separate from the DC Universe, and the early episodes make references to Superman and other heroes as fictional, along with their alter egos. The show's first season also has a cruder animation style and more focus on problems that would afflict urban youth whereas the Lighter and Softer later seasons would shy away from this and make the conflict more about fantastic superhero problems.
The original pilot episode had a more detailed animation style, along with character design differences (Garnet's hair is straight and down and she wears a looser-fitting outfit, Amethyst wears a fanny pack, wears nail-polish, and has sleeves, and Pearl looks NOTHING like the final product, more closely resembling David Bowie's character Ziggy Stardust). Lars (who is darker skinned and has black hair) and Steven mutually dislike each other, while in the final product Steven is nothing but friendly to a sardonic Lars. Pearl is presented more as an older sister than a maternal figure and neither she nor Garnet are above teasing or calling out Steven. The episode also implies the Gems eat food, while (as mentioned below) only Amethyst normally does.
The first few episodes had all of the Gems being shown to eat and like food, including Pearl (who outright says she likes pie in one episode). Later on, it is established that their species doesn't require food, with Amethyst's regular eating simply being recreation. Meanwhile, Garnet is willing to eat on rare occasions and Pearl was changed to actually dislike eating intensely. The discrepancy in relation to Pearl was later hand-waved by one of the writers, saying that Pearl likes the process of making pie.
Similarly, the Gems are shown gasping for air when surfacing at the end of "Cheeseburger Backpack", but by "Island Adventure" thirty episodes later, they forbid Steven from coming along on a mission because it's underwater and he's the only one who needs to breathe.
Garnet is more enigmatic and less helpful in early episodes, rather than a confident leader that freely gives advice. Meanwhile, Amethyst and Pearl were more self-absorbed before falling into their more sisterly and maternal roles, respectively.
The mid-point of the first season revealed most of the seemingly-random monsters the Crystal Gems had been fighting are formerly sapient Gems that were corrupted. This leaves a few minor creatures much stranger because this origin clearly does not apply: "Together Breakfast" has Garnet disposing of a living scroll that turned into living smoke when burned* One of the writers implied the scroll was painted with ink made from crushed gem shards, but that doesn't explain the implication that the image was a Brown Note. He eventually deleted said post, rendering it questionably canon anyway., and Amethyst and Pearl carry in giant bird's egg (which a gem monster would definitely not lay). The old Gem ruins in "Cheeseburger Backpack" are overrun with small creatures called Crystal Shrimp, which seem to be an actual species instead of unique organisms like Gem monsters. In "Lion 2: The Movie", some kind of crystal lizard left behind a carcass that Lion eats instead of being reduced to a gem when its body was damaged.
In early episodes, gems were described as "dying" or being "killed" before the terminology was changed to "shatter", due to shatting the gemstone being the only way to actually kill them: anything less just forces them into a regeneration state.
This trope is referred to in-series in one episode, where Amethyst mentions how weird it is that the ''Lil Butler" had a cat in the pilot instead of a dog.
Super Friends 1973–74 season. The first episode "The Power Pirate" has a number of things that don't match later episodes.
Wendy and Marvin talk like 1960s hippies, using phrases like "groovy", "cool", "right on" and "far out". They never speak like this again.
Marvin is able to levitate himself into the air, indicating that he is developing super powers. This is never brought up again.
Wonder Woman controls her transparent plane by beaming mental thought waves at the control panel. In all later episodes she controls the plane with a standard control yoke.
Wonder Woman can fly through the air, which she never does in any of the later episodes.
The Superjail! pilot "Bunny Love" depicts the Warden as being well aware of the Twins and their trouble-making, while Jared suggests that he "suspend their privileges". The Twins are also later shown to fear the possibility of dying from the outcome of the chaos, and rather than teleport away, they fly off on rocket-powered stair climbing machines. In the series itself, the Warden and Twins never really meet face to face and he either seems to be unaware of the chaos they make or doesn't acknowledge it. Other than a reference to them being inmates in a tie-in comic in Playboy magazine, the Twins are also later treated as a separate division of characters from the staff and inmate population.
The colors in the pilot are a little less saturated, particularly visible in the Warden's outfit (which is a brighter or darker purple in later episodes).
A few of the characters had different vocal delivery in both the pilot and season 1: Jared was less shrill and seemed to have a bit of a lisp, while Alice had a deep voice but wasn't as guttural.
The pilot uses the song "Rubber Bullets" by 10cc. Starting with "Superbar," the theme was changed to "Coming Home" by The Cheeseburgers, as the licensing fee to use the former song was too expensive.
The ending credits to the pilot are also a little more comprehensive and accurate with the voice actors for the show. For some reason or another, the voice acting credits in season 1 only ever credited Chris McCulloch, David Wain, Teddy Cohn, and Richard Mather, and never changed or updated by episode. Seasons 2 and 3 fix this mistake, save for a few occasional slip-ups (such as Sally Donovan being uncredited in "Oedipus Mess").
The Superman Theatrical Cartoons seem to be aired Out of Order as one of them contains Superman leaping instead of flying. Afterwards he is presented as flying as jumping around looks awkward in animation. The shorts are the earliest examples of Superman flying instead of leaping. The series also presents some weirdness for Superman in general. His parents are nonexistent, instead he was raised in an orphanage, and most of the villains are rather generic because the shorts came out before the modern concept of "comic book villains" and "super villains" was made concrete.
The first syndicated season of Teenage Mutant Ninja Turtles (1987) cemented the familiar look and sound of the series, which stayed largely consistent until the show was retooled in 1994. As a result, reruns of the 1988 season and especially the 1987 miniseries always seemed like strange anomalies. The animation style was different, the Channel 6 building was different, and some of the voices were different (although the actors were the same). One of the most obvious shifts was Krang. He seemed more alien in the early episodes, with slow, labored speech, pulsating flesh, and constantly twitching tentacles.
The original seasons of Thomas the Tank Engine were not only produced using models compared to the CGI animation of today, but were fairly low budget and prone to errors compared to the later points. Also the depiction was incredibly different due to being based very closely on The Railway Series novels, the tone was darker, the functions of the railway were more realistic (drivers talked and had a more pivotal role, and there were often life like accidents and collisions that were made as spectacular as possible) and some of the characters played more as Unsympathetic Comedy Protagonists (Thomas in particular was far more self absorbed and rude in the first two seasons, a fairly lengthy number of seasons developing him into the altruistic Cloud Cuckoo Lander he is in the CGI episodes). The series started to become more like it is today when Moral Guardians started to complain about both the amount of violent crashes, and the lack of female characters, leading directly to the creation of Emily.
In the ThunderCats (1985) pilot it's debatable whether the Wilykittens were cubs or simply small cats, as they're treated less like children than they are later on. There's also ambiguity in their relationship as Wilykit tells Wilykat "Gosh, you're beautiful when you snarl" without a lick of sarcasm or familial affection. Also, the characters spent their time before they got to Third Earth naked, their modesty protected by Barbie Doll Anatomy. After they got their outfits, they spent the rest of the series in them.
The sixth produced episode "Hero Hamton" actually had Calamity Coyote in an antagonistic role toward Buster and the others (collaborating with Monty, no less) when most later episodes would have him as one of their good friends. For that matter, Plucky was far more of a Jerkass in said episode than in most of his later appearances. (Which, by Plucky's standards, says a lot, really.)
The early Tom & Jerry cartoons are much slower paced than the later ones. In their first cartoon Jerry has no name and Tom is called "Jasper". Also, Tom looks and acts more like a real cat by walking on all fours and meowing whenever he's in pain instead of his later more infamous human yell.
Toot & Puddle: I'll Be Home for Christmas was a special commissioned before the series was made for TV. As such there are some notable differences between it and the TV series, including a different animation style and art design, different voice actors, and a different feel of pacing that includes an unusual frequency of scene changes.
The first episode of Total Drama Island, the first season of the Total Drama series is like this to newer viewers, since Chris is a lot more subdued and kinder, while the contestants are a lot more chummier with him. Then again, this is before he became the sadistic Chris we all know and put them through the hellacious torture he calls challenges. Also, when the contestants are faced with the first of many ridiculous challenges, DJ, of all people yells "Oh shit", which is largely out of character. Geoff and DJ would also join Duncan in tormenting Harold. Later on in the first season, Geoff and DJ are established as nice guys.
In the first episode of the original cartoon, the Autobots could fly just like the Decepticons. This ability faded over the course of the first season.
The series also had a degree of Negative Continuity (characters changed as the toy company demanded, but there was zero focus on consistency otherwise.) and was written by writers who often didn't know each other's work and were on a very tight schedule. Therefore, every episode, New Powers as the Plot Demands came and never appeared again, game-ending weapons were made or discovered and then forgotten, no two backstory-related episodes were compatible with any of the others, and the show's terminology didn't exist yet; sparks, protoforms, anything else about the Cybertronian life-cycle - all that debuted in Beast Wars, and Negative Continuity means these things didn't just work differently than they do now - they didn't exist. Also, while most TF series are either arc-based or Half-Arc Season-structured, the original had a few multi-part episodes, but a Story Arc or Myth Arc? You'll have to wait for Beast Wars. Megatron was a very different character than his successors, too, having a high-pitched voice and being prone to yelling "Decepticons, retreeeeat! RETREEEEEEEAT!" when the going got tough sometimes when he still had the upper hand. Starscream was The Starscream, but had none of the subtlety or Magnificent Bastard quality - he'd openly insult Megatron and his plans, and even attempted to shoot him more than once, getting away with it only because, again, this isn't the Megatron you know. (This isn't to say it sucked, but it was very much an 80s cartoon, and also, much of what we consider integral to the TF universe now hadn't been invented yet, and didn't even have equivalents or things you could see evolving into those concepts, and even the anatomy of a TF series was different. This comes together to make watching the original TF for the first time a very trippy experience.)
The show completed ignored the "robots in disguise" element that would later characterize the franchise, meaning that the existence of the Transformers is public knowledge and both sides commonly walk around urban areas in broad daylight without attracting attention. There's also the fact that several Transformers can inexplicably change size when they transform (Megatron turning into a handgun and Soundwave turning into a tape player, for example), something that would rarely come up in later fiction, the highly non-canonical origin of the Transformers and the even more outdated origin for Unicron. Let's just say Transformers has come a long way since 1984.
The series had a characters popping guns out of hidden panels in their vehicle modes in the pilot. This effect was dropped for all characters except those whose vehicle modes had visible weaponry (Starscream, Megatron, Shockwave, and Vehicons with jets as their altmode), which was surprising given that there was a line of toys featuring hidden weapon gimmicks for the different characters in vehicle mode.
The decepticon mooks, Vehicons, are much more effective in the pilot, probably because the only named Decepticons were Megatron, Starscream, and Soundwave. 5 of them successfully capture Cliffjumper. 2 of them actually come close to defeating Bumblebee and Arcee - the pair are saved by Bulkhead's appearance and the cons escape unarmed. Never again do the Vehicons display such competence; each Autobots plow through dozens of them with little to no effort.
The first season of Ultimate Spider-Man was a lot more reliant on Peter Parker addressing the audience and making Cutaway Gags. These were toned down by the following season, which also bumped up the focus of Spidey teaming up with other heroes in the Marvel universe.
The first Underdog cartoon has little in common with the others. He has a noticeably different voice. The narrator doesn't speak until midway through the episode. There's no Sweet Polly (it remains the only cartoon she's not in), no villain, no Cliffhanger, and Underdog is a completely moronic, bumbling idiot Jerkass who demolishes two banks to rescue a boy trapped in a bank vault (at first, Underdog goes to the wrong bank by mistake). The rest of the series portrays Underdog as much more competent. The first few cartoons are also completely self-contained. The four-part episodic structure wouldn't begin until the fifth cartoon ("Go Snow").
The first three installments of VeggieTales used a Two Shorts format (which would eventually return from time to time) instead of being single half-hour episodes, and were named after their primary theme instead of the actual stories. Where's God When I'm S-Scared? opened with an actual child reading the letter instead of Bob or Larry paraphrasing it, the second short had a nameless female narrator instead of Bob or Larry, and Larry's voice was radically different. God Wants Me to Forgive Them!?, the second installment, didn't even have a "Silly Songs" segment; instead it bumpered its shorts with a commercial for the "Forgive-O-Matic".
The pilot episode is the only episode animated in Adobe Flash.
Various characters are drawn differently than the rest of the show. The Monarch has a different crown. Brock has a unibrow in some shots, is shorter and has skinnier legs than his later appearances. Dr. Girlfriend has different facial features.
The pilot is the only episode in which Professor Impossible is voiced by Peter McCulloch.
The earliest Woody Woodpecker shorts directed by Walter Lantz and Alex Lovy are quite different from the eventual Jerkass he became later. Woody was adorned with an ugly, ghoulish design, and was a shameless ripoff of the early screwball Daffy Duck (Mel Blanc was even the first voice of Woody). Even the stories and gags were very derivative of Warner Bros.–type comedy (although this is probably because Lantz had one of their former writers, Ben Hardaway, working with him).
X-Men: Cable was introduced as a present day mercenary who used to work for the new dictator of Genosha, meaning all the stuff about him being a time traveling freedom fighter from the future wouldn't be established until later episodes. He also inexplicably had two arms in his first appearance, and didn't sport his trademark cyborg prosthesis until subsequent episodes.