Being the very first installment in the Pokémon franchise, Pokémon Red and Blue has a lot of features that were either absent, changed, or phased out in later entries.
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Game Mechanics
- The game mechanics are much more opaque than in later generations. Neither the game or the manual explain things such as same-type attack bonuses; that a move's type determines whether it is physical or special; a move's attack power and what it even does; that dual-typing can result in double weaknesses, double resistances, or even cancel out to neutral damage; and so on. Even Nintendo's official strategy guide for the game neglects to mention these aspects. Later generations present all of the aforementioned information (and more) up front.
- Held items, Abilities, and Natures do not exist yet. Held items were introduced in Gen II, while Abilities and Natures were introduced in Gen III, with every mainline entry since making use of these mechanics (with the exception of Pokémon Let's Go, Pikachu! and Let's Go, Eevee!, which are intended as simplified introductions to the series, and Pokémon Legends: Arceus, which changes up the battle mechanics in several other ways too).
- There's only one Special stat, covering the job that both Special Attack and Special Defense have from Gen II onwards. This had the side-effect of Pokémon with a high Special stat being able to dish out powerful Special moves while taking little damage from them in return. This also means that Gen I moves that would go on to specifically alter either Special Attack or Defense, such as Amnesia, originally just raised or lowered Special as a whole.
- The Elemental Rock-Paper-Scissors had a number of oddities:
- Psychic-type Pokémon. Thanks to a programming error, they're immune rather than weak to Ghost attacks in Generation I, leaving them with a weakness to only Bug-type. Not that it would have mattered much if the error wasn't present, as neither typing had much in the way of offense power during this gen. The only damaging Ghost-type attack that wasn't a Fixed Damage Attack was Lick (which was only 20 base power at the time) and the only Ghost-types in the game (the Gastly line) were weak to Psychic thanks to being dual-type Poison; meanwhile, the Bug-type attack Leech Life was only 20 base power as well, leaving the player with only Pin Missile and Twineedle... which the most powerful Bug-types in the game couldn't even learn, and the only one that could, Beedrill, was also dual-type Poison.
- Ice does neutral damage to Fire-types instead of being resisted.
- Bug and Poison are both super effective against each other. Starting in Gen II, Poison would resist Bug, while doing neutral damage back.
- Dragon-types are programmed to be super-effective against themselves, but this never sees use since the only damage-dealing Dragon-type move in Gen I is Dragon Rage, a fixed damage attack that always does 40HP.
- Steel, Dark, and Fairy don't yet exist as typings. Steel and Dark were added in Gen II to Nerf Psychic-type Pokémon (the former resists Psychic damage, while the latter is immune) and buff Fighting types. Fairy would be added in Gen VI to nerf Dragon and buff Poison.
- There are a few differences in how status ailments function:
- While Paralysis and Burn cut speed and attack, respectively, as they do in later generations, the stat change is stacked into the normal stat modifier instead of being its own thing. This has the unintended side effect of Rest not removing the stat drop when it cures the status.
- Sleep can last up to seven turns rather than five (Generations II to IV) or three (Gen VII onwards), you cannot attack the turn you wake up, and it's possible to wake up on the same turn it is inflicted.
- Fire-types, Ice-types, and Electric-types could all be inflicted with their respective status ailments (burn, freeze, paralysis) in Gen I. Fire-types and Ice-types wouldn't become immune until Gen III, while Electric-types didn't become immune until Gen VI.
- Due to how infliction for status effects worked, damaging moves that inflict the Paralysis, Burn, and Freeze status effect could not inflict their status on Pokémon of the same type as the move. Which meant Normal-types couldn't get paralyzed by Body Slam, Ghost-types wouldn't get paralyzed by Lick, etc. This did not apply to pure status moves though, meaning Thunder Wave could still paralyze Electric-types and the powder moves could inflict their status on Grass-types. The Poison status in general was also exempt from this, meaning the Bug-type move Twineedle would still poison Bug Pokémon, but not Poison-types (who were immune to the status even in Gen I). Gen II would address this for paralysis, making Normal-types no longer immune to paralysis from Body Slam, Ghost-types no longer immune to paralysis from Lick, etc, however it did not fix it for burn and freezing, leading to the oddity where Tri Attack could burn Fire-types and freeze Ice-types. This would be truly fixed in Gen III.
- The Freeze effect was even more grating in Gen I, as the victim had no way to thaw out naturally or even thaw themselves out. The only ways to fix it during a battle were to use a status healing item or hope that the opponent would be foolish and/or gracious enough to do the deed themselves by using Haze or any Fire move that could inflict the burn status. And just like Sleep, Frozen Pokémon couldn't act on the turn that they thawed out.
- Instead of the Effort Values system that mainline Pokémon games have used since Gen III (with few exceptions), Gens I and II have the Stat Experience system. When it comes to accumulating Stat EXP, instead of each Pokémon giving 1-3 EVs in certain stats upon being knocked out, you gain Stat EXP in every stat equivalent to the knocked out Pokémon's base stats; EVs cap at 252 effort points per stat (255 in Gens III to V), while Stat EXP caps at 65535 per stat. When it comes to converting them into the actual stat boost, EVs are simply divided by 4, while Stat EXP is instead squared and then has the result divided by 4. While this all works out to both systems boosting a stat by up to 63 points at level 100 when maxed out, there's one vital distinction: the EV system gives a Pokémon an overall EV cap of 510, meaning the player must engage in Min-Maxing for competitive play. In contrast, the Stat EXP system has no overall cap, so you can max out all of your Pokémon's stats without penalty, removing any need to have your Pokémon specialize.
- While still working out to have nearly the same level of effect as IVs in later gens, Individual Values in Gens 1 and 2 are on a scale of 0 to 15 (which then gets mulitplied by 2 to determine the stat boost given at level 100), rather than having the 0 to 31 scale with no multiplying used in all later Gens; the only other game in the franchise to use a 0-15 scale is Pokémon GO. Meanwhile, the HP IV is dependent on other stats; all future games, including GO, have HP determined separately.
- The likelihood of getting a Critical Hit is based on the Pokémon's base Speed stat. In addition, moves with an increased critical hit ratio (such as Slash) increase the chance of one by eightfold instead of just doubling it. The end result of both these things is that all but the slowest Pokémon in the game are nigh-guaranteed to land critical hits when using said moves, and even when not using them, have base critical rates of 20% or more. Critical hit rates are also much higher in general, with even the slowest Mons having critical hit rates around 10%, when later generations would go on to make critical hits a base 6.25% chance for all Pokémon (Gen VII onwards would reduce it farther to 4.17%).
In addition, a bug causes critical hits in Gen I to ignore all stat modifiers, positive or negative, for both the user and opponent. Meaning that if you use Swords Dance twice and then get a critical hit, you'll actually do less damage than if you didn't get one. - Certain Badges grant a permanent 12.5% boost to a corresponding stat to your Pokémon in battle, so by the end of the game, all your Pokémon's non-HP stats will have a 12.5% boost in battle. This, combined with trainer Pokémon not having Stat Experience, means the drastic level jump at the end from Giovanni to the Elite Four isn't actually as severe as it looks, as this boost means you can have the same exact Pokémon ten or so levels lower and still have better stats than the opponent's equivalent. The mechanic of Badges granting a permanent stat boost would be kept in Gens 2 and 3 (albeit slightly nerfed in the latter to a 10% boost), before being dropped altogether from Gen 4 onward.
Due to a programming bug known as the "stat modification glitch," this stat boost is reapplied every time a move alters your Pokémon's stats in battle, making this even more overpowered in Gen 1, as essentially any stat-boosting move would boost all of your stats that have the corresponding badge boost. - When trying to catch Legendaries or Pokémon in the Safari Zone, expect to see "You missed the POKéMON!" instead of the standard "Oh, the POKéMON broke free!". The equivalent of 0 shakes in these games is just dodging the ball entirely, even when asleep or eating. Additionally, the number of times the ball shakes on a failed capture is always the same, loosely based on an approximation of the odds of catching the Pokémon. Later games have the amount of shakes be independent of the likelihood of capture, using "shake checks" on failed captures to determine how many times the ball should shake.
- You are unable to catch any Pokémon if your current PC box is full, requiring you to manually switch to a new one. You also aren't told when you've filled up your box, meaning you can try to catch a Pokémon only to get a sudden text box saying that you can't. In Gen II, Bill calls you whenever you filled up a box, while Gen III onwards automatically switch boxes without you having to do anything.
- Your bag only had 20 inventory slots, with a limit of 99 for each item. You could have more than 99 of a single item, but that would result in multiple stacks of it. The item limit also included key items. Generation II onwards would start giving you separate pockets for different item types for better organization, which each pocket having their own item cap, with the caps in general slowly increasing until being removed altogether in Generation IV, which also resulted in the removal of the Item Storage System (which itself was capped at 50 inventory slots).
- Some key items can only be obtained by registering a certain number of Pokémon as caught in the Pokédex and then speaking to one of Professor Oak's aides, who are scattered around Kanto: the HM for Flash requires 10 Pokémon, the Itemfinder requires 30, and the Exp. All requires 50. Starting with Generation II, HMs and key items are generally received either automatically during the main story or simply by talking to an NPC, and later generations began to make them all obtainable through unmissable NPC interactions and other plot events. The only games to bring back the "must own a certain amount of Pokémon to receive item" mechanic were the remakes and the Let's Go games, the latter of which placed much greater emphasis on catching lots of Pokémon anyway.
- Your team is not automatically healed when entering a Player Versus Player battle, nor are they healed after beating the Elite Four. They also aren't automatically healed when you take them out from the box.
- For a long time, these games remained the only installment in the series in which it is possible to migrate Pokémon back from their sequels, though you'd have to delete moves that didn't yet exist. From Gen III onward, until the Nintendo Switch era, transferring Pokémon forward to the next generation is a one-way trip.
- Pokémon given by NPCs (such as Lapras) will be automatically sent to the PC if your party is full. Later games require having an empty slot in your party before you can receive them, save for Pokémon Sun and Moon (which are quite inconsistent in this regard).
- AI opponents have unlimited PP; consequently, stalling is impossible in single-player battles.
- All status moves and debuffs have 75% accuracy when used by the AI, which makes some (such as Hypnosis, normally 55% accurate) hit more often and others (such as Growl and Leer, normally 100% accurate) hit less. This would be kept in Gen II, but in all following generations, the accuracy of AI moves don't play by any different rules.
- Once you're done trading or battling another player, you can't return to the Pokémon Center normally. Instead, you must reset the game to continue from where you left off.
- If a Pokémon gains multiple levels at the same time, it will not learn any moves that it otherwise would have from any of the levels it skipped. This is corrected in all future generations.
- The AI decides and makes its actions when it's their Pokémon's turn to move, not before the turn starts like the player. As such, if you're fighting a trainer with the "Good AI" flag and switch your Pokémon out to one they have a super-effective move against, they'll get to pick the super-effective move after your Pokémon has been sent out. Additionally, this means when their Pokémon acts second in battle, they can use items and switch out their Pokémon after your Pokémon has already made its move, when normally these actions are supposed to occur at the start of the turn before everything else. The latter will rarely come into play as few AI opponents are programmed to be able to switch at all and those that can do it randomly, but the former means if your Pokémon goes first and brings their Pokémon's health low or inflicts a status, the AI can immediately respond with an item to recover their Pokémon's health or heal the status.
Moves and Items
- Moves with a 100% hit chance will still fail 1/256 (0.4%) of the time, with fans referring to this quirk as a "Gen 1 Miss". In the original Japanese version, this even applies to Swift due to a glitch making it behave like a 100% accurate move rather than an Always Accurate Attack, meaning it was also susceptible to accuracy-modifying moves like Sand-Attack. In future generations, Swift and other moves that avoid accuracy checks only miss if the opponent is in the "semi-invulnerable stage" of a two-turn move like Dig or Fly.
- Fixed Damage Attacks not only ignore Elemental Rock-Paper-Scissors, but also bypass full type immunities; this wouldn't be the case from Gen II onward. This is also the only generation that introduced any of these attacks.
- HM moves have to be done manually, meaning that you have to access your Pokémon from the menu and select whatever HM they learned. From Gens II to VI, you're automatically asked if you want to use the HM required when in front of an obstacle that requires its use (Strength for boulders, Cut for trees, and Surf for any body of water).
- Using an Escape Rope or the field move Dig in a cave or dungeon warps the player to the last Pokémon Center they healed at, rather than the entrance as in later games.
- X Accuracies in Gen I and II allow your Pokémon to ignore accuracy checks entirely, making even One-Hit KO moves always hit. This was severely nerfed in future games, instead increasing accuracy by one or two stages, and OHKO moves would ignore the accuracy boost entirely.
- Evolutionary stones are bought at the department store (except for the Moon Stone, of which there are several hidden throughout the game.) Later games would make them much more scarce and difficult to obtain.
- Struggle is treated as a Normal-type move, so Ghost-types are immune to it. This can potentially make a PvP battle Unintentionally Unwinnable if both players' last Pokémon is a Ghost with no PP left. Future generations make it a type-less move to avoid this. The recoil damage from struggling is also treated differently, with the Pokémon taking half the damage they managed to deal. Gens II and III would reduce it to a fourth of the damage, while Gens IV onward would make it a fourth of your max HP, regardless of how much damage you inflicted.
- Multi-hit moves like Pin Missile use one check for critical hits, instead of doing so each hit separately. This means if the first hit crits, every hit will.
- Many moves have different power, accuracy, and even typing from later games.
- Dig has 100 base power; Gen II would lower it to 60 BP, while Gen IV would raise it up to 80 BP.
- Blizzard has 90% accuracy, instead of the 70% it would have in all future Gens. Additionally in the original Japanese Red and Green, it had a 30% chance to freeze; Japanese Blue and international Red and Blue would immediately nerf this to a 10% chance.
- Wing Attack had 35 base power, making it identical to Peck, despite it being a move that is learned at rather high levels. Gen II would buff its power to 60, and later Gens would generally make the move get learned at substantially lower levels.
- Gust and Karate Chop are Normal-type moves instead of Flying- and Fighting type, respectively, such they would in all future generations.
- Some moves lack the secondary effects they gained in later games. Rock Slide and Waterfall cannot flinch, Dizzy Punch cannot confuse, and Tri Attack cannot inflict status ailments.
- Hyper Beam would skip the recharge turn if it knocked the opponent out, making it a high risk, high reward move that sees extensive use in competitive play. Pokémon Stadium would remove this quirk and force the recharge turn regardless of if the opponent faints, which all future Gens would keep for Hyper Beam and all its deriatives, making the move notoriously impractical.
- Reflect and Light Screen only remains active as long as the user is on the field, ending immediately when they faint or switch out, instead of remaining active for the entire party for a set number of turns as in future generations. The move also doubles the user's appropriate defensive stat instead of lowering the attacker's offensive stat during the damage calculation.
- Disable will affect one of the opponent's moves at random, instead of the last one they used, like in all later generations. Because of this, it can work on the very first turn, as opposed to failing if used before the opponent has had a chance to attack.
- Instead of copying the last move the opponent used, Mimic instead allows you to copy any move they know by opening a separate menu that allows you to pick one of them. This also has the side effect of instantly allowing you to see what moves the opponent knows.
- One-Hit KO attacks will always fail if the user is slower than the target, whereas from Generation II onwards, such attacks will always fail if the user is at a lower level than the target. The user also does not get an accuracy bonus based off the difference between the user's and target's level like in later games.
- Counter has a lot of quirks. It only works from being hit by a Normal- or Fighting-type attack, can hit Ghost-types despite being a Fighting-type move, is capable of countering moves that hit a Substitute, and works based on the last time damage was dealt rather than if the opponent did a damage-dealing move that turn (meaning it can be used multiple times off a single hit, and can even be successfully used off an attack that just KOed an ally after switching the replacement in).
- Bide ignores accuracy and evasion, can hit foes during the semi-invulnerable periods of Dig and Fly, hits Ghost-types despite being a Normal-type move, will last either 2 or 3 turns instead of a set 3, and will not be disrupted by sleep.
- When Rage is used, it would lock the user into only using Rage until they were knocked out or the battle ends, with all other options being locked out, including the ability to switch or run away. Being incapacitated from Sleep, Paralysis, etc, would only pause usage of the move during the turn(s) the user was unable to act, resuming to only using Rage again when they regained the ability to act. Also only the initial usage of Rage would consume PP, and so the move could go on infinitely without ever running out of PP.
- Using trapping moves (Wrap, Bind, Fire Spin, Clamp) completely immobilized the target until the attack wore off after 2-5 turns... immobilizing meaning that they couldn't attack, not that the player couldn't switch them out. The user was also stuck using said trapping move for the same duration as well. This was changed from Gen II onward to just be an effect that deals extra damage after every turn and prevents switching out until the move wears off, with both Pokémon being able to take other actions.
- Roar and Whirlwind can only be used to escape from wild battles and have no effect in trainer battles. In later generations, they force the opposing trainer to switch Pokémon.
- Substitute has a lot of oddities that were fixed in the same generation by way of Pokémon Stadium:
- It does not block Paralysis and Sleep inflicted from status moves, but does block status infliction from the secondary effects of damaging moves like Body Slam. On the flip side, it blocks the Confusion status from status moves, but does not block it from the secondary effects of damaging moves like Psybeam, so longs as the Substitute wasn't broken by the attack.
- If a Pokémon with exactly 1/4 of its HP attempts to make a Substitute, it will succeed and then promptly faint rather than prevent you from doing the move.
- If a Pokémon uses Selfdestruct or Explosion on an opponent's Substitute and breaks it, the exploding Pokémon will not faint or take any self-inflicated damage at all (though its sprite will still disappear). Similarly, if a Pokémon breaks an opponent's Substitute with Hyper Beam they will not have to recharge the next turn.
- If a multi-hit move breaks an opponent's Substitute before it ends, breaking the Substitute will instantly end the move and not continue on to damage the opponent.
- Super Fang and trapping moves will bypass Substitute and hit the user as usual.
- Leech Seed will bypass a Substitute and latch onto the opponent as usual, and a Pokémon behind a Substitute can be flinched from its Substitute being hit by flinching moves.
- If a confused Pokémon is behind a Substitute and tries hitting itself in confusion, it will instead hit the opponent's Substitute if they too have one up. If the opponent doesn't have one, the confused Pokémon won't hit itself nor its Substitute.
- The TM list is weird. TMs generally consist of moves that have high offensive/defensive value, invoke status ailments, or allow for unique battle strategies. In Gen I, while there is some of that, much of the list also consists of really weak and basic attacks (such as Rage, Bide and Water Gun), those with low competitive viability (such as Fissure), and just plain odd additions (like Chansey's Signature Move Softboiled, which only it and Mew could learn). There are also poor type variety, such as Fire Blast being the only Fire TM, meaning most Fire-types are stuck with just Ember for most of the game due to learning Flamethrower late in the game or never at all.
- In general, Normal seems to have been the default assumption, as opposed to future generations, where it tends to be treated as one type among many.
- Normal-type attacks are a lot more common. A total of 78 moves, nearly half of all moves, are Normal-type. The next most common, Psychic, only boasts fifteen, followed by Water and Grass with nine, Fighting and Poison with eight, Ice and Flying with six, Fire, Electric, and Ground with five, Bug with four, Ghost with three, Rock with two, and Dragon with one. This means that several types do not possess a reliable attacking option.
- Several moves that would be considered a different type in other generations, like Karate Chop, Gust, Sand Attack, and Bite, are Normal-type. What's more, Normal also boasts a number of moves that seem like they should be a different type (for instance, Comet Punch or Razor Wind) but are classed as Normal anyway.
- Several Pokémon did not learn any attacking moves of their own type through leveling up. Pinsir and Scyther didn't learn any Bug moves, Voltorb and Electrode didn't learn any Electric moves, Rhyhorn and Rhydon didn't learn any Rock nor Ground moves, etc. TMs were able to provide for some, but the aforementioned lack of variety still left certain Pokémon with no options. Gen II began to expand move pools and offer more varied TMs, and it is now unheard of for a Pokémon not to naturally learn at least one move of its own typing.
- In Red and Blue, Caterpie and Weedle couldn't learn Harden upon evolving into Metapod and Kakuna, despite Harden being the iconic ability of both cocoon Pokémon. Additionally, wild Metapod and Kakuna didn't have any attacks but Harden. Both of these were changed as early as Yellow.
- Despite being well-known for flying Ash around in the anime and even being the flying Poké Ride in Pokémon Sun and Moon, Charizard could not learn Fly until Yellow.
- Dragonite similarly couldn't learn Fly despite even its sprite depicting it flying, and it took until Gold and Silver to correct this. Dragonite didn't get Wing Attack either, which combined with the fact that Dragon Rage was the only Dragon move, left Dragonite with no STAB moves in its debut generation.
- Tangela couldn't learn Vine Whip until Yellow.
- Lickitung couldn't learn Lick until Yellow.
- Koffing couldn't learn Poison Gas until Gold and Silver, despite being the Poison Gas Pokémon.
- Unlike in all future generations, it is possible to do zero damage. Whenever this occurs, the game will display it as a miss, regardless of whether the move actually hit or not. This can be most easily demonstrated by catching a Weedle and attempting to use Poison Sting against Brock's Pokémon; unless you've done some serious grinding, it will miss every time, despite being a 100% accurate move. In subsequent games, even the weakest moves are rounded up to 1 HP of damage.
- Signature Moves in most future generations tend to be abnormally powerful or at least fairly unique, if not the primary selling point of its user. That's the case for some first-generation signature moves (Spore, Super Fang, Hi Jump Kick), but just as many of them are weirdly underpowered. Barrage, the signature move of the Exeggcute line, for instance, is just a nameswap of the useless-outside-of-the-earlygame Fury Attack—Exeggcute doesn't even get STAB on it. Alakazam's signature move of Kinesis is a single-stage accuracy drop that has only 80% accuracy itself. Hitmonlee gets three signature moves (Rolling Kick, Jump Kick, Hi Jump Kick), with one being a worse version of the other. Even some stronger ones, like Raticate's Hyper Fang, Seaking's Waterfall (newer players are likely shocked Waterfall is a signature move at all), and Kangaskhan's Dizzy Punch, are strictly inferior to moves they can already learn by TM or level-up. And then there's the case of Softboiled, which is traditionally the Chansey line's signature move—except it's a TM, and Chansey can't learn it by level-up, meaning that the TM essentially exists just for Chansey and Mew. In general, it seems like the assumption was that signature moves were more for fluff than actual power.
Pokémon
- Pokémon themselves seem to be a relatively new thing, with them being separate from normal animals. Professor Oak sends you out to catalogue Pokémon because no one really knows exactly how many of them there are, which is brought up by various NPCs. There's a general air of mystery surrounding various Pokémon, their evolutions, behavior, and where they came from. Later games establish that Pokémon are the animals of this universe, and researching them has been a profession since long before Professor Oak.
- No Pokémon except for Nidoran have a defined gender. Most of these Pokémon will have a gender assigned to it if traded to Generation II (or transferred to Pokémon Bank in the case of the Virtual Console releases); in later generations, only certain Pokémon, such as most (but not all) Legendary and Mythical Pokémon, are genderless. In addition, male Nidoran and female Nidoran were classified as different species. Pokémon introduced later, after genders were introduced, would classify male and female Pokémon with the same name as the same species, even if they have drastically different appearances and gameplay traits. Meowstic and Indeedee, for instance, have their males and females considered the same species, even though they have differences comparable to male and female Nidoran.
- Legendary Pokémon aren't treated as they would be in later generations:
- In Generation I and their remakes, they are completely detached from the game's plot and are there solely as extras. Even Mewtwo is relegated to journal entries in the Pokémon Mansion that you don't have to read. Pokémon Crystal was the first to actually incorporate them into the story, and even then they weren't the main focus.note From the third generation on, Legendary Pokémon became a major plot element, being at the core of the antagonists' plans and/or required to resolve the situation.
- They just hung around in places associated with their types (Articuno and Zapdos) or in locations that have nothing to do with themselves (Moltres and Mewtwo). It wasn't until Generation II that Legendary Pokémon were given designated places to be or, if the legends fit, would roam about. FireRed and LeafGreen moved Moltres to Mt. Ember, a volcano, giving it a more fitting location, similarly to the other members of its trio.
- The box art for the Gen I don't show the game's resident legendary, but instead the final evolution of a starter Pokémon (Charizard for Red, Venusaur for Green, and Blastoise for Blue) or just the starter in general (Pikachu for Yellow). This is retained in the remakes.
- You can get a legendary Pokémon pretty early in the game. From Gen III onward, you aren't able to get a legendary until at least the sixth gym. In the Gen I games and their remakes, it's possible to go out of your way and challenge Koga as your third gym, so long as you're fine with running around in Rock Tunnel without any light, which allows you to reach the locations of Articuno and Zapdos. Who are Level 50 when your own Pokémon would be in the high 30s if you did do things in the intended order. If you're playing Let's Go Pikachu/Eevee, you don't even have to fight Koga. In the Gen 2 games, you can also catch members of its legendary trio before beating the fourth gym... but they require so much luck to even encounter and then are so absurdly hard to catch when you do find them that you're better off not even trying.
- From Gen II onward, each box legendary would have a signature move or ability that only it could have (for example, Ho-Oh and Lugia got the exclusive moves Sacred Fire and Aeroblast, respectively). It would take until Gen V for a first generation legendary to get their own signature move, that being Mewtwo with Psystrike.
- None of the legendaries have their own unique battle music. Instead, it's just the regular wild Pokémon theme. While Gen II gave the legendary beasts their own themes, it wouldn't be until Gen III that all legendary Mons would have distinct battle music. note
- Pikachu hadn't been fully cemented as the series mascot when the original Red and Blue released, so it lacked the Popularity Power it would receive in later gens and was mostly treated as any other non-evolved Pokémon. Even in Yellow, where Pikachu is the starter and prominently displayed on the box art, all the starter Pikachu got was the inability to evolve (leaving it worse than regular Pikachu by lategame), a slight move reshuffling that only added Light Screen to its movepool (useless on it since it's a Glass Cannon), and the ability to learn Surf from Pokémon Stadium (actually a huge boon for an Electric type in a gen where most movepools are awful, but still not enough to save the line from being outclassed by better Electric types). It wasn't until the next generation that Pikachu's signature item Light Ball was introduced, and it continued to gain special treatment in each generation onward.
- Due to predating the series' Earth Drift, some Gen I Pokémon had Pokédex entries or general lore referencing real-life animals and locations:
- Mew is said to have been found in Guyana, South America in its Pokédex entry and the Pokémon Mansion journal entries. Let's Go Pikachu and Let's Go Eevee would retcon Mew to have been found in an unspecified jungle.
- Lickitung's, well, tongue is compared to that of a chameleon's in Red, Blue, and LeafGreen.
- Arcanine's Pokédex entry in Yellow says it's legendary in China. Let's Go would change it to say that it's legendary in the East instead of specifically mentioning China.
- Old entries for Raichu back in Gen I would indicate its electrical prowess was potent enough to harm an Indian elephant, a notable real world species.
- The very earliest Pokémon programmed into the game tended to look more like generic fantasy monsters than any real-life animal, often with a somewhat saurian or kaiju-esque bent. Rhydon, the first ever, bears little resemblance to a rhino aside from having a horn, Kangaskhan is pretty similar but with a pouch, and the Nido family's only obvious animal inspiration is maybe Baragon. Pokémon designed later on, or appearing in the following games, tend to be more clearly based on real animals or have obvious mythological origins (and even the latter is mostly reserved to Legendaries and Pseudo-Legendaries), with the generic monsters falling by the wayside.
- With Pokémon Red and Blue, this manifests in a couple of Pokémon names, both in English and Japanese:
- On the English side, the names "Mr. Mime" and "Geodude" as particular standout examples feel very out of place these days (especially since genders were introduced in the next generation, and yes, both of them can be female), and it seems the only reason Mr. Mime's pre-evolved and evolved forms, Mime Jr. and Mr. Rime, are called such was to keep up the pattern, no matter how strange it feels.
- A few Gen I Pokémon are named after specific celebrities: For example, Hitmonlee's English name is based on Bruce Lee and its Japanese name (Sawamular) is named after Tadashi Sawamura, a famous Japanese kickboxer. Hitmonchan's English name is derived from Jackie Chan and its Japanese name (Ebiwalar) comes from World Champion Boxer Hiroyuki Ebihara. Gen II continued this practice when it came to Wobbuffet, whose Japanese name "Sonansu" and habit of raising its arm to its head recalled the catchphrase and signature gesture of the deceased celebrity Hayashiya Sanpei. It was probably the legal debacle involving Kadabra and Uri Geller (Kadabra's Japanese name, Yungerer, and its spoon-bending shtick was based on him and he promptly sued for defamation) and the general Earth Drift that took place early on that led to this naming convention no longer being practiced.
- On the Japanese side, one gets the feeling they weren't even trying with some of the Generation I names (such as the legendary birds being called "Freezer,"note "Thunder,"note and "Fire"note ) and it was only from Gen II onward that this changed and effort consistently happened. Though the English translators changed those names, that didn't stop the translators from coming up with new names that were just creatively spelled variations of common English words, and sometimes not even that, such as "Persian", "Abra", "Kadabra", "Alakazam", "Golem", "Slowpoke", "Krabby", "Electrode", "Koffing", "Weezing", and "Ditto", in addition to some names which were just two words put together without making a portmanteau out of them, such as "Beedrill", "Ninetales", "Sandshrew", "Sandslash", "Vileplume", "Bellsprout", "Geodude", "Voltorb", "Marowak",note "Seaking", and "Magikarp".note . This naming style is also somewhat present in Gen 2, with names such as "Bayleef", "Ledyba", "Hoothoot", "Unown", and "Lanturn". Later generations avoid using regular or misspelled English words, though with a few exceptions.note Portmanteau names seem to have become the norm.
- Pokémon lay eggs... except that one of the journal entries found in the Pokémon Mansion says "Mew gave birth. We named the newborn Mewtwo." This was unchanged in FireRed and LeafGreen, which feature breeding, but the Let's Go games instead say they "obtained a new Pokémon" from Mew.
- The sapience of Pokémon was dubious in the first generation. Several Pokémon, such as Lapras, are specifically noted for being able to understand humans, signifying this is uncommon for Pokémon. Trainers using whips (even pacifistic ones like Sabrina) also implies that Pokémon are treated more like wild animals. Over time, Pokémon as a whole have become more anthropomorphic in intelligence as well as in personality.
- Aerodactyl is the only extinct Pokémon to be revived from something other than a fossil — instead being revived from Old Amber — and was the only extinct Pokémon to be a single-stage evolution until Generation VIII. It is also the only fossil Pokémon without a counterpart: all later generations would have fossils come strictly in pairs, with there being two pairs in Gen VIII.
- Many of the Pokémon sprites in Red, Green, and Blue are blatantly Off-Model, barely even resembling their early artwork, much less later art. From Yellow onward, the in-game appearances of every Pokémon match their artwork and merchandise. Unlike in future generations, the official artwork came after the Red and Blue sprites, with series artist Ken Sugimori being tasked to take said sprites and create the final character designs using them as the basis.
- Several Pokémon had many human-like features in their designs, such as having hands like humans (five fingers and all) or in Machoke's case, looking entirely human sans the head. While Pokémon in later games would still have humanesque features, they are much less pronounced.
- Jynx has black skin in Generation one, and the Japanese versions of Generation 2, before the decision was made to change its appearance due to complaints of looking similar to a blackface caricature. Starting with the international releases of Gold and Silver, Jynx is now edited to have purple skin, and any rereleases of older games and episodes featuring Jynx are recoloured the same way.
Battle Interface
- There is no visible Experience Meter during battle. The only way to check how close a Pokémon is to leveling up is to check its stat screen.
- There are no Circling Birdies to signify when a Pokémon is Confused. An animation featuring a question mark is shown instead, with said animation reusing that of the move Amnesia, which is a stat-raising move that has nothing to do with confusion.
- There is no Poké Ball icon during wild Pokémon battles to mark that you already caught that Pokémon. This was added in Gen II and is thus present in these games' remakes such as FRLG and Let's Go!.
- There's no graphical effect for Pokémon that are frozen solid.
- Pokémon that are affected by the Burn status would be indicated by the skull and crossbones graphics, the same sprite used for the Poison effect. This would be changed by using fire sprites to indicate a Pokémon that was burned.
NPCs and Player Character
- Normal NPC Trainers do not have actual names; you're just told what their Trainer class is. All other games, including Gen I remakes, give the Trainers names.
- Lt. Surge's title is "Lightning American" and his official backstory describes him as being a former officer and pilot in the United States army. Later games would replace America with Fantasy Counterpart Cultures of several different parts of the real US, such as the Arizona-based Orre, the New York City-inspired Unova, and the Hawaii-derived Alola. An NPC even lampshades this in Pokémon Black 2 and White 2, wondering if Lt. Surge is actually from Unova. The reference to the United States is kept in all of Lt. Surge's later appearances until Pokémon Let's Go, Pikachu! and Let's Go, Eevee!, which would finally change his title to "Lightning Lieutenant" in the English translation and "Lightning Tough Guy" in the Japanese version.
- Numerous trainers are depicted as carrying whips (Cooltrainers, Tamers, Rocket Grunts, Cue Balls, Sabrina) as a holdover from when Pokémon were intended to be treated in-universe as more violent monsters rather than powerful pets. All future games removed them, except for the Tamer class in the remakes.
- Unlike future installments, the Pokémon League Champion is not established as the leader of the Elite Four. Instead, the Elite Four is led by the member who faces the challenger last, namely Lance. Generation I and their remakes were also the only generation until Generation IX where the League Champion is The Rival; and even then, they aren't the Top Champion you need to defeat in order to receive the rank yourself, as you need to defeat the chairwoman of that region's Pokémon League instead.note
- The Elite Four do not have their own unique theme, recycling the regular trainer battle theme (barring Lance, who has the gym battle theme). Gen II would have them use the gym battle theme, before future generations would give them a unique track.
- Almost every trainer's Pokémon lineup is of uniform level, e.g., if one of a trainer's Pokémon is Lv. 20, they will all be Lv. 20. The only trainers with Pokémon of varying level are Gym Leaders, the Elite Four, your rival, and Giovanni. In all future generations, any trainer's lineup may have level variance.
- Trainers in the first two generations generally have more Pokémon than those of later generations. Three Pokémon is the most common number, and four and even five Pokémon lineups are pretty widespread. Single-Pokémon trainers are much rarer than in later games (where they're practically standard.)
- There are a handful of trainers throughout the game that use the starter Pokémon families. After Gen 1 the starters don't appear anywhere else outside of your rival(s) and the characters who give you your starters in the first place, with the notable exception of the Terarium, where they can be found in the wild.
- There was only one Gym Leader, Misty, who explicitly wasn't an adultnote , while later generations would tend to have equal numbers of both teenage and adult Gym Leaders. Gym Leaders also tended to be a lot ruder in Generations I and II, as opposed to be more amicable ones of latter generations.
- Brock had a defense focus in Gen 1, with his unique TM (Bide) being a counter attack move. Starting in the Gen 3 remakes his dialogue about defense was dropped, and his signature move was changed to Rock Tomb, an offensive Rock attack.
- Gen I is the only generation with no female protagonist. Starting with Kris in Gen II's Crystal Version, every game has had both a male and female option. Early official art shows a female character hanging out with Red and Blue, but said character was never intended to be playable (Satoshi Tajiri claims he just felt the Power Trio imagery looked neat), while Capsule Monsters era artwork show a different female character who went far enough to have sprites done before ultimately being scrapped. Her design would see use in the spin-off material like Pokémon Adventures before seeing use in the GBA remakes as female player option (Leaf), and in Let's Go as an NPC (Green).
- The human character designs are noticeably grounded compared to future generations. Most NPCs have relatively realistic Japanese designs with hair colours in either brown, black, or colours that are stylized versions of those colours and their designs aren't that "out there". The wildest designs are Misty and Lance, who are still normal-looking people. It wasn't until Gold and Silver that the games began embracing Anime Hair and more flamboyant clothing for their characters.
- In the Japanese version, the Coffee Man is passed out drunk. Since Gen 1, the games have avoided alcohol references.
- Team Rocket had some odd quirks when they were first introduced:
- Compared to the other villainous teams in future games, Team Rocket are just The Mafia; not only do they openly admit to being a criminal organization, they also brag about how they're able to abuse Pokémon and use/sell them for profit, with making money being their only real goal. If Team Rocket wins, they'll... secretly run one of the biggest companies in the Kanto region and maybe have a powerful lab experiment at their beck-and-call as an enforcer. Later villainous teams introduced to the franchise would have deeper motives concerning their crimes, a fair number would see their end goals as noble, and the consequences of them succeeding is the usually the death of every person and Pokémon in the region.
- Team Rocket lacks a unique battle theme in Gen I and uses the generic Trainer battle theme. It wasn't until Gen 2 where they were given their own unique battle theme. The GBA remakes kept the Rocket battles with generic themes for consistency.
- Aside from Giovanni, there were no unique Team Rocket members. It wasn't until Gen II where Grunts got both female and male designs, with male and female Executives also being introduced. Later games would follow a similar trend. FireRed and LeafGreen went back to having all Grunts being the generic male with females and only a few Executives showing up in the post game, while Let's Go instead replaced some of the existing male grunts with females, including replacing the Rocket Brothers in Silph Co. with the Rocket Sisters.
- The Pokémon used by all trainers, including important trainers such as Gym Leaders, the Elite Four, and the Rival, will have the four latest moves that said Pokémon would learn at their level, just like a wild Pokémon would.note When combined with the generally barren natural learnsets of Gen I, you get some ridiculous and rather ineffective movesets, even with endgame trainers. This includes Giovanni's Rhydon only knowing a single damaging move in Stomp (which was Normal type at that), and two One-Hit KO moves; Lorelei's Slowbro not only still having Water Gun, but also being its only damaging move; Lance's Aerodactyl and Dragonite only having Normal-type moves, meaning that they'd be unable to harm a Ghost-type Pokémon; and Champion Blue's Exeggutor only knowing three moves, with both of its only damaging moves again being Normal type (Stomp and Barrage). In later games, Pokémon used by Gym Leaders and other important trainers would either have customized moves involving plenty of TMs and Egg Moves that follow a specific strategynote or at least have an assortment of varied damage dealing moves with type coverage in mindnote . In fact, this was changed as soon as Yellow: Giovanni's Rhydon knows Rock Slide and Earthquake, two powerful STAB moves, same with Lorelei's Slowbro knowing both Psychic and Surf, while Lance's Aerodactyl knows Flying-type moves and his Dragonite has the terrifying combo of Fire Blast, Thunder and Blizzard.
Music
- The wild battle theme of Gen I games and their GBA remakes are the only ones to retain a constant frantic air. All later arrangements of the song would contain a more lighthearted, joyous section to break up the tension.
- In Red and Blue, when the bike is in use, the bike music always plays on the overworld, even when moving to a new area. Yellow changed this so this music doesn't play on Route 23 or in Victory Road, but its usage is otherwise the same in that game.
- Catching a Pokémon in Gen I will continue playing the battle theme after the jingle finishes. Later generations switch to the wild-battle victory theme.
- When you trade a Pokémon, the background music still plays, when later generations have the evolution theme play in its place.
- Not every member of the Elite Four uses the same battle music: Lance uses the Gym Leader battle music, while Lorelei, Bruno, and Agatha use the regular trainer battle music. Later games (including the Generation I remakes FireRed, LeafGreen, Let's Go Pikachu, and Let's Go Eevee) have all four Elite Four members using the same battle music.
Miscellaneous/Unsorted
- The "evil team" plot isn't as intertwined with your Pokémon League challenge as they would be in future generations. While later games regularly alternate your badge quest with progressing the storyline, here only Sabrina and Giovanni are gated behind the plot; the former requires you to end Team Rocket's Silph Co. takeover, while the later requires you to have every other badge in the game (meaning Team Rocket needs to be defeated by proxy). As such, four of the game's Gym Leaders can be fought (Lt. Surge, Erika, Koga, and Blaine) while completely ignoring everything to do with Team Rocket.
- Some of the gyms have unique quirks that haven't shown up at all in future titles, such as Erika only allowing girls in her gym and Blaine locking the door and hiding the key. There are also gyms that don't have aesthetics to reflect the type they focus on, something that would become far more prominent in later games.
- There's very few cutscenes in the game, generally only when dealing with your rival or Giovanni. It gives the game more of an organic feel compared to the sequels.
- Red, Green, and Blue all have completely identical plots, with the only difference between the paired versions being the exclusive wild Pokémon. Later games would have different mascot legendaries that play a major role in the plot, with the Hoenn, Unova, Galar, and Paldea games having more significant differences.
- There are regular references to Real Life locations which now seems odd due to the Earth Drift that the series underwent in later installments. For example, a Silph Co. employee complains that he's being reassigned to the Tiksi branch, calling it "Russian no-man's land".
- In the Kanto games, the "badge check" gates are its own dedicated route (Route 23, to be precise). Later games have the "badge check" either be a smaller area at the end of the route before Victory Road, or a single individual situated either before or after Victory Road.
- The Silph Scope is required in order to see and identify Marowak's ghost in Pokémon Tower so you can progress with the plot. Without it, Marowak's ghost effectively blocks you from reaching the final room, as your Pokémon will be too scared to attack it.note While the concept of needing to uncover the actual form of a Pokémon would reappear in future entries, the idea of your Pokémon being "too scared" to attack an opponent is exclusive to these games and their remakes.
- How this game handles Ghost Pokémon is very different from any other. The Silph Scope is required to see them in the wild, otherwise they appear as "ghosts" and cannot be interacted with. The only trainers that use them are Mediums, and most of them are being outright possessed by their own Gastly. Gen 2 put them more in line with the other types, even giving them a relatively normal gym.
- If an NPC Trainer switches Pokémon, the experience distribution can become flaky. For example, you send out Pokémon A while your opponent sends out Pokémon X. You immediately switch to Pokémon B, while your opponent switches to Pokémon Y. Pokémon B defeats Pokémon Y. The NPC trainer then sends Pokémon X back out. Pokémon B defeats Pokémon X. In all future games, Pokémon A will still get a share of experience after the defeat of Pokémon X. Here, however, Pokémon B will get 100% of the experience. As very few NPC trainers are programmed for switching and those few that can will do it randomly for no rhyme or reason at that, you will probably never run into this, but it is weird nonetheless.
- The notion that "Red" and "Blue" are the canonical names for the player character and his rival was not established until Gold and Silver. Early official materials, such as Nintendo's official strategy guide, tend to use the names "Ash" and "Gary", like the anime.
- The Pokémon League is implied to be a new thing; most players interpreted Lance's dialogue to mean that your rival was the first Trainer to ever beat the Elite Four, though he never directly says this. Let's Go Pikachu/Eevee would have Lance explicitly say that while your rival wasn't the first to beat the Elite Four, this is the first time that fighting the previous Champion is mandatory.
- Pokémon Yellow is unique among Pokémon games for several reasons. Firstly, it's a fourth version made after an Updated Re-release third version (Japanese Blue) was already created, something which would never happen again. Secondly, its biggest design differences are based on the anime, meaning that it is a rare example of the mainline games using elements of the anime and effectively serving as an advertisement for the anime instead of the other way around. Thirdly, it's the only main series game that doesn't give you a choice of starter until Pokémon Let's Go, Pikachu! and Let's Go, Eevee!, which are remakes of this title.
- In the Kanto games, Lt. Surge mentions a Great Offscreen War that happened that he was involved with. The war has never been clarified upon since. Considering the original games were much more Earth-like, he's likely discussing a real-world war (likely the Gulf War, the most recent war involving the US at the time).
- The locales were extremely basic in design where most of the buildings were copy-pasted and the majority of the routes were just straight roads with the usual patches of grass and maybe a side area or two that contained an item. Even the unique locations like the Seafoam Islands and Power Plant didn't stand out much other than the legendary Pokémon that were there. Later games would start using more unique designs for the buildings, added more unique dungeon areas, and made most of the routes have more points of interest in between them.
- Kanto is the only Fantasy Counterpart Culture region to share a name with its real-world inspiration. Outside Japan, the name "Kanto" also wasn't stated in-game; until Pokémon Gold and Silver, all non-Japanese Pokémon media simply referred to the region as the "Pokémon World". Even in Japan, the name "Kanto" appears exactly once in-game (on the Town Map in your rival's house in Pallet Town). In later English media, such as Pokémon Journeys, while it's still spelled the same, it's pronounced slightly differently: Pokémon's Kanto uses the short "a" sound, as in "cat" or "bad," whereas Japan's Kanto uses more of an "ah" sound, as in "taco" or "khan."
- The Kanto League has the unusual title of "Indigo League", possibly because it's also the only league whose Elite Four serves two regions. After Gen II, all future leagues (both mainline and spin-off) are named after their respective regions (Hoenn League, Sinnoh League, etc) and serve only that locale.
- Pokémon names are consistently pluralized with an "s" at the end. For example, Weezing's Pokédex entry mentions that "2 Koffings can fuse into a Weezing over many years". Later Pokémon media has the plural forms of Pokémon names the same as the singular, as with moose and sheep — the rare exceptions to this can be considered errors.
- Kanto is laid out in an odd way compared to later regions. Immediately after Mt. Moon is a one way gate, stopping the player from returning to earlier locations until beating Misty and it's possible to easily bypass the Seafoam Islands by flying back to Pallet Town and surfing South. It also gives a choice of two routes to reach Fuchsia City. Later Generations never lock the player out of previous areas and are laid out so visiting all routes is necessary for progression.
