History Main / OneGameForThePriceOfTwo

* Fictional, action figure version: [[Series/MysteryScienceTheater3000 Johnny Longtorso, the Man Who Comes In Pieces]]. Which is actually a parody of those British model magazines that sell you a part with each issue, requiring you to [[GottaCatchEmAll collect them all]] if you want to finish your model.

* ''VideoGame/MyPokemonRanch'' is a "companion app" to ''VideoGame/PokemonDiamondAndPearl'', essentially a glorified storage closet. While you can play it standalone, as Hayley brings a new Pokémon to the ranch [[PlayEveryDay daily]], you'll need to connect your DS to unlock the biggest ranch, see all the Pokémon, and transfer rare Pokémon back to your own game.

* In an odd variation, ''VideoGame/Sonic3AndKnuckles'' actually ''was'' one game that was split in half to meet time constraints. The first half, ''Sonic the Hedgehog 3'', contains the first six zones, and the second half, ''Sonic & Knuckles'', contains the last five zones and an [[AnotherSideAnotherStory additional campaign]] with Knuckles. The ''Sonic & Knuckles'' cart came with a slot on top that allowed it to use what was called "Lock-On Technology" -- placing ''Sonic 3'' inside the slot would combine the two carts into the complete ''Sonic 3 & Knuckles'', unlocking Knuckles' ''Sonic 3'' levels and the hidden [[InfinityPlusOneSword Super Emeralds]].

* In an odd variation, ''VideoGame/Sonic3AndKnuckles'' actually ''was'' one game that was split in half to meet time restraints. The first half, ''Sonic the Hedgehog 3'', contains the first six zones, and the second half, ''Sonic & Knuckles'', contains the last five zones and an [[AnotherSideAnotherStory additional campaign]] with Knuckles. The ''Sonic & Knuckles'' cart came with a slot on top that allowed it to use what was called "Lock-On Technology" -- placing ''Sonic 3'' inside the slot would combine the two carts into the complete ''Sonic 3 & Knuckles'', unlocking Knuckles' ''Sonic 3'' levels and the hidden [[InfinityPlusOneSword Super Emeralds]].

* As a whole, this tends to happen a lot in Japan. DVD sets tend to have a pitiful two episodes per disc, despite being able to carry far more with just a single one. Presumably, this started with the Laserdisc (which only has the capacity to hold two episodes), but carried over even as media became more expansive to maximize profits. On the other hand, the standalone [=DVDs=] tend to have ludicrous amounts of {{bonus material}}, comparable to a LimitedSpecialCollectorsUltimateEdition, justifying the cost for die-hard fans. Localized releases, when they aren't one-to-one with the original, usually split the difference and sell the whole series in a single set -- as was the case with, for example, ''Anime/SuzysZooDaisukiWitzy''.

* Strangely, the Japanese DVD releases of ''Anime/SuzysZooDaisukiWitzy'' is hit by this - the first season is released across two volumes. The American release, however, combined both volumes into a single disc.
** As a whole, this tends to happen a lot in Japan. DVD sets tend to have a pitiful two episodes per disc, despite being able to carry far more with just a single one. Presumably, this started with the Laserdisc (which only has the capacity to hold two episodes), but carried over even as media became more expansive to maximize profits.

* Fictional, action figure version: [[Series/MysteryScienceTheater3000 Johnny Longtorso, the Man Who Comes In Pieces]]. Which is actually a [[DeconstructedTrope deconstruction]] of those British model magazines that sell you a part with each issue, requiring you to [[GottaCatchEmAll collect them all]] if you want to finish your model.

** This is lampshaded in an early mission, on either game; whichever version you are playing, you get a short piece of dialogue with what's implied to be the protagonist of the other version, in which the Decepticon tells the Autobot that "we may be on different sides, but we're both still playing the same game."

* ''Tokimeki Memorial Pocket'', the UpdatedRerelease of ''[[VisualNovel/TokimekiMemorial Tokimeki Memorial : Forever With You]]'' on Game Boy Color, has two versions : the Sports one, subtitled "Koutei no Photograph" (Campus' Photograph), and the Culture one, subtitled "Komorebi no Melody" (Melody of the Sunlight Filtering Through The Tree). They're the same game, aside from the fact the cast is divided in half between the two versions (including the three new characters), the clubs are divided between the two versions depending their nature (Sport-type or Culture-type), and an additional club visiting sequence in the prologue.

* In 2015, Creator/ArcSystemWorks released ''Dragon Ball Z: Extreme Butōden''; the following year, it released ''One Piece: Grand Pirate Colosseum''. While both of them were stand-alone fighting games, a later patch allowed crossover cross-play between both titles.

* The ''[[VideoGame/PokemonStadium Pokémon Stadium]]'' games aren't actually an example of this trope, but they're still considered this by the fanbase from a gameplay perspective. While you don't ''need'' to have a copy of a mainline titles to 100% complete any of the games, all the rental Pokémon you're provided if you don't connect one generally have bad stats and mediocre move sets that make beating the harder fights with them a ridiculously hard SelfImposedChallenge; especially in regards to the [=N64=] entries. In addition, every installment rewards you with items that you can transfer back to the main games, as well as exclusive Pokémon with unique movesets that you can't get anywhere else (such as Surfing Pikachu) if you [[NintendoHard complete several absurdly difficult challenges]].

* ''VideoGame/{{Medabots}}'', a [[{{Mons}} Mon]] series featuring children playing with alien robots rebuilt into toys (no, really) did this. The first three generations of the game subverted it with the Parts Collection games, which were just a series of battles allowing you to get a complete collection of Medals and Parts without having to trade, wrapped in a flimsy ExcusePlot.

* The original release of ''VideoGame/YokaiWatch'' only came as one edition, but ''Yo-Kai Watch 2'' learned from Pokémon's success and was first released as ''Bony Spirits'' and ''Fleshy Souls'' which had exclusive {{Mons}}, and then ''Psychic Specters'', which at least gave a NewGamePlus option for people who already cleared one of the first two versions. The same goes for the ''Yo-Kai Watch Blasters'' spinoff (which was split into ''Red Cat Corps'' and ''White Dog Squad'' versions, a third ''Moon Rabbit Crew'' version was added later but as a free update for the first two), ''Yo-Kai Watch 3'' (''Sushi'', ''Tempura'', and later ''Sukiyaki''), and ''Yo-Kai Watch Blasters 2'' (''Sword'' and ''Magnum''). In the case of ''Yo-kai Watch 3'' though, the international versions instead combined all three games into one, averting this. ''Yo-kai Watch 4'' also plans to avert this, planning a single version for Nintendo Switch.

* A handful of the ''Franchise/{{Digimon}}'' portable games do this. Notably, ''Cathode'' and ''Anode Tamer'', and ''Digimon World Dusk'' and ''Dawn''.

* ''Franchise/{{Pokemon}}'' is the TropeCodifier, with each game in a pair having exclusive Pokémon or certain ones with differing rarities. While other aspects such as story and gym leaders [[VersionExclusiveContent are occasionally played with]], these differences in ''Pokémon'' remain a constant. If you [[GottaCatchEmAll want to catch them all]] and complete the Pokédex, you'll need to trade version exclusive Pokémon with other players, as well as Pokémon that ''only'' evolve via trading (of which there are several, with a few having additional conditions that need to be met as well). From [[VideoGame/PokemonDiamondAndPearl Gen IV]] onward, the series has had the ability to trade over the internet via the "Global Trade System", allowing a player to collect all the Pokémon without knowing someone with the other version personally or buying it yourself. The system initially had the annoying limitation of only allowing the player to search for Pokémon they already had registered as "seen" in their Pokédex, but later games would allow you to simply type in the name even if you haven't seen them yet on that file.
** ''Pokémon'' also occasionally has "third versions" released shortly after each new pair of games, which are {{updated rerelease}}s that combine elements of both versions while adding new ones. However, these games mix-and-match the version-exclusive Mons lists, meaning that players of the third version will often need to trade with ''both'' previous versions to get a handful of remaining creatures and complete their Dex. Later on, even these third versions would come in pairs, though [[VideoGame/PokemonBlack2AndWhite2 the first instance of this]] actually served as direct sequels.
* ''VideoGame/PokemonMysteryDungeon'' has also dabbled in this. The ''[[VideoGame/PokemonMysteryDungeonRescueTeam Rescue Team]]'' games justified it somewhat by having each version released on different systems. Instead of directly trading Mons, these games use a password system instead, which means anyone with an internet connection or guide book doesn't really need to interact with someone owning the other copy. The ''[[VideoGame/PokemonMysteryDungeonExplorers Explorers]]'' games also got an updated release that gives access to the exclusive Pokémon from both versions without the need for these passwords. The third set of ''PMD'' games were NoExportForYou titles for UsefulNotes/WiiWare and were '''One for the Price of Three''', with the interesting feature of being able to use the same save file for all three so long as you're playing on the same UsefulNotes/{{Wii}} (thus allowing to access to all the different Pokémon and dungeons). All subsequent PMD games like ''Gates'' and ''Super'' would avert this entirely by being single releases, including the remake of the ''Rescue Team'' games.

* ''Franchise/{{Pokemon}}'' is the TropeCodifier, with each version having exclusive Pokémon or certain ones with differing rarities. While other aspects [[VersionExclusiveContent are occasionally played with]], the differences in ''Pokémon'' remain a constant. You'll need to trade both version exclusive Pokémon with other players as well as Pokémon that ''only'' evolve via trading in order to complete the Pokédex. From [[VideoGame/PokemonDiamondAndPearl Gen IV]] onward, the series has had the ability to trade over the internet via the "Global Trade System", allowing a player to collect all the Pokémon without knowing someone with the other version personally or buying it yourself. The system initially had the annoying limitation of only allowing the player to search for Pokémon they already have registered as "seen" in their Pokédex, but later games would allow you to simply type in the name even if you haven't seen them yet on that file.
** ''Pokémon'' also occasionally has "third versions" released shortly after each new pair of games, which are {{updated rerelease}}s that combine elements of both versions while adding new ones. However, these games mix-and-match the version-exclusive Mons lists, meaning that players of the third version will often need to trade with ''both'' previous versions to get a handful of remaining creatures and complete their Dex.
* ''VideoGame/PokemonMysteryDungeon'' pushes this further to the extreme. The first set of games were at least released on different systems, but the second set give absolutely no reason for the double release. Trading is not an option here, so all but one of the few differences in Pokémon listings are solved by entering passwords which are far easier to find online than in the opposite version. It basically boils down to whether you wanted Mewtwo or Celebi after you've beaten the game. The third Mystery Dungeon (NoExportForYou) is One for the price of Three, and interconnectable with each other because they would all be on the same Wii. ''Explorers of Sky'' subverts this by having every Pokémon except Arceus available without any interaction at all, partially because the game uses a completely new password system that does not work with the previous games. Later PMD games like ''Gates'' and ''Super'' would also avert this by sticking to only one game instead of having different versions.
** The remaster for the ''Rescue Team'' games, ''Pokémon Mystery Dungeon: Rescue Team DX'' for the UsefulNotes/NintendoSwitch, would avert this entirely. Only one version of the game was released, and it even included features and Pokémon from later MD games.
* The ''[[VideoGame/PokemonStadium Pokémon Stadium]]'' games are considered this by the fanbase, as while you don't ''need'' to have a copy of your own handheld game to 100% complete any of the games, all the rental Pokémon you're provided if you don't connect a mainline game (especially in the [=N64=] titles) generally have bad stats and mediocre move sets that make beating the harder fights with them a ridiculously hard SelfImposedChallenge. In addition, some installments do reward you Pokémon with unique movesets that you can't get anywhere else, such as Surfing Pikachu, if you [[NintendoHard complete several absurdly difficult challenges]].
* The [[Anime/{{Pokemon}} anime]] did this with the first fifth-generation-based movies, ''[[Anime/PokemonTheMovieBlackAndWhite Black: Victini and Reshiram]]'' and ''[[Anime/PokemonTheMovieBlackAndWhite White: Victini and Zekrom]]''. Just like [[VideoGame/PokemonBlackAndWhite the games]], they are two versions of the same movie, with similar plots, but with Reshiram and Zekrom's roles swapped and a few different Pokémon appearing in the different movies. Averted when it came to the home media release, as both movies were released together in a 2-disc DVD set... outside the Australian and New Zealand markets, at least.

** ''Pokémon'' also occasionally has "third versions" released shortly after each new pair of games, which are {{updated rereleases}} that combine elements of both versions while adding new ones. However, these games mix-and-match the version-exclusive Mons lists, meaning that players of the third version will often need to trade with ''both'' previous versions to get a handful of remaining creatures and complete their Dex.

** ''Pokémon'' also occasionally has "third versions" released shortly after each new pair of games, which are {{updated releases}} that combine elements of both versions while adding new ones. However, these games mix-and-match the version-exclusive Mons lists, meaning that players of the third version will often need to trade with ''both'' previous versions to get a handful of remaining creatures and complete their Dex.

* ''Franchise/{{Pokemon}}'' is the TropeCodifier, with each version having exclusive Pokémon or certain ones with differing rarities. Other aspects are occasionally played with, though: the major examples being the main installments of [[VideoGame/PokemonRubyAndSapphire Gen III]] have the antagonists differ between the games[[note]]''Ruby'' and ''Omega Ruby'' have Team Magma attempting to increase the planet's landmass, while ''Sapphire'' and ''Alpha Sapphire'' have Team Aqua desiring to increase the size of the oceans. ''[[UpdatedRerelease Emerald]]'' has both villain teams in play, actively fighting each other and the player character in order to reach their respective goals.[[/note]] and [[VideoGame/PokemonBlackAndWhite Gen V]] having a differing final town and Gym Leader, in addition to each version having their own exclusive locations. Regardless, from [[VideoGame/PokemonDiamondAndPearl Gen IV]] onward, the series has had the ability to trade over Wi-Fi via the "Global Trade System", allowing a player to collect all the Pokémon without knowing someone with the other version personally or buying it yourself. The system initially had the annoying limitation of only allowing the player to search for Pokémon they already have registered as "seen" in their Pokédex; later games would allow you to simply type in the name even if you haven't seen them yet on that file.
** There are some critters the player can only get by trade evolution - ''no one'' can catch them in the wild. Alakazam, Golem, Scizor, Steelix (until Generation IV), Machamp, Kingdra, Politoed, and the list goes on.
** Mythical Pokémon. The game technically doesn't require them for OneHundredPercentCompletion, though it will acknowledge if you went the extra mile to pick them up. The reason they don't count for completion? They're event-exclusive Pokémon that usually can't be gotten through normal gameplay. Instead, you have to attend special events, connect online at certain locations or certain time periods, among other things, to be either be given the Pokémon directly as a gift or gain an item which starts a short side-quest to access them. Much worse than Mythicals are other types of Event Pokémon, which are one-of-a-kind variants of typical mons. While Mythical Pokémon will always re-enter rotation every few years, event Pokémon like the Spiky-Eared Pichu or Ash Pikachu never return.
** Pokémon brought this to an extreme in its third generation, due to technical limitations meaning all your Pokémon from the first two generations couldn't be transferred to these new games, so older players had to start all over again alongside new ones. So, how did you get all the Pokémon in Gen III? Your best method, if you didn't have a friend who owned some of these games, was to pick up both ''Ruby and Sapphire'' for about half of them, both ''[=FireRed=] and [=LeafGreen=]'' for most of the other half, and a copy of ''[[VideoGame/PokemonColosseum Colosseum]]'' and ''[[VideoGame/PokemonColosseum XD: Gale of Darkness]]'' for the remaining few. If you're gunning for Mythical Pokémon, European and Australian players also had to buy ''Pokémon Channel'' and connect it to their GBA games to get Jirachi... which might be an improvement over America and Japan, which could only get the Pokémon through preorder-only version of ''Colosseum''. That makes six-to-seven games depending on your region, one of them having to be preordered, across two consoles, for HundredPercentCompletion.
** The GTS in ''Diamond and Pearl'' aside, collecting Generation IV's massive list was further complicated (ignoring the GTS's obvious limitations) by the fact that in order to even see a Manaphy, one must physically import it from ''[[VideoGame/PokemonRanger Pokémon Ranger]]''... which could only be done once per cartridge (not save file), so if you got a used copy, you were screwed. This was rectified in ''Platinum'' and later games, which allow the player to see a picture of Manaphy in books sitting around in certain locations, registering Manaphy as "seen" and enabling the GTS route. For those without near friends who own a copy, don't even think about trying to get a Spiritomb without the GTS in Gen IV. This near-impossible-to-achieve-alone feat requires meeting 32 players in the underground (or the same one person thirty-two different times), which can only be done through local multiplayer.
*** ''Pokémon Yellow'' lacked Pokémon you could only get in ''Red'' AND only in ''Blue'', so if you bought ''Pokémon Yellow'', you also needed to trade with BOTH ''[[VideoGame/PokemonRedAndBlue Red and Blue]]'' to get certain Pokémon. The release of ''VideoGame/PokemonGoldAndSilver'' alleviated this somewhat with use of the Time Capsule; ''Silver'' and ''Crystal'' both have all the Pokémon that can't be found in Yellow, and also make it easier to obtain multiple Eevee and the other Tyrogue evolution, meaning if you can trade with one of those, you only need another RBY player for the fossil you didn't pick. You still need two other games, but it's not limited to only ''Red'' and ''Blue''. Of course, this is offset by giving you access to the three starters without trading and some overall updates, basically sacrificing easier 100% Completion for a better gameplay experience. ''Emerald'' and ''Platinum'' pull the same trick, but without that trade-off.
** ''[[VideoGame/PokemonBlack2AndWhite2 Black 2 and White 2]]'' as well. This is the first time a pair of "third versions" were announced (''Blue'' and ''Yellow'' were released at different times in Japan). It should be noted, however, that these games are sequels rather than the usual rereleases.
** ''VideoGame/PokemonSunAndMoon'' introduces Cosmoem, a Pokémon that evolves into either one of two different options depending on which version is played. ''Sun'' players evolve it into Solgaleo while ''Moon'' evolves it into Lunala. In addition, Rockruff will evolve into a different form of Lycanroc (Midday or Midnight, respectively) depending on which version is played. However, the Lycanroc forms are not version-exclusive; they can be obtained, at rare quantities, in the opposite games.
** ''VideoGame/PokemonSwordAndShield'' has two gyms which change depending on which version of the game you play. ''Sword'' players face Fighting specialist Bea and Rock specialist Gordie while ''Shield'' players face Ghost specialist Allister and Ice specialist Melony. The DLC expansion passes are also split into two separate versions specific to each version of the main game, including a different rival appearing on the Isle of Armor.

** ''VideoGame/DevilChildren''. Like in ''VideoGame/TheLegendOfZeldaOracleGames'', the story is different depending on what version you first.

** Ditto for ''VideoGame/Persona2'', which predates the ''DDS'' above. All the choices you made in ''Innocent Sin'' will affect some minor things in ''Eternal Punishment''; Tatsuya and Katsuya's names will change depending on what you put Tatsuya's name as, Tatsuya and Apollo will carry over their stats, and dialogue will change. However, most players out of Japan never got to experience the full duology in that manner, because due to NoExportForYou, the two games for them are on different consoles.

* The now-defunct company Smilesoft is probably the KING of this trope: All of their monster-collection [=RPG=]s had two versions. The ''VideoGame/{{Telefang}}'' series came in Speed and Power versions, each focusing on {{Mons}} with that attribute, ''VideoGame/{{Bugsite}}'' had Alpha and Beta versions and the ''VideoGame/DinoDevice'' games came in Dragon and Phoenix versions.

** Battle Network 4 also involved a rare chip called the Z-Saver. This chip can only be obtained by linking up your game boy to a ''VideoGame/MegaManZero 3'' game. However, each ''Zero 3'' cartridge only contained one copy of the Z-Saver chip, meaning that not only did you have to find another game, you'd also have to find one that hasn't been tapped of its chip (making rental store copies completely worthless, as their chips have already been gutted and put into their own ''Battle Network'' games). This basically meant that if you wanted the chip, you ''had'' to buy another game.
*** Made worse (or better, depending on view) that said game is of a completely different genre (and a very hardcore iteration of said genre to booth!), so while it is vastly different and thus is not "more of the same", it also means that there were good chances that ''Battle Network'' players wouldn't enjoy the needed game at all.

* The doujin game ''VideoGame/MagicalBattleArenaNEXT'' plays with this: while two versions were released (''Fantasy World Side'', featuring ''VideoGame/TouhouProject'' characters and stages and ''Magical Girl Side'', which had characters and stages from various MagicalGirl works), the latter one was released later. Both can also be combined together for a more complete game.

* ''VideoGame/FireEmblemFates'' follows this trope, with each version being the same up until the sixth chapter, when it will then branch off into a different story and gameplay depending on which version the player is playing: ''Birthright'' has the player align with the peaceful Hoshido kingdom with opportunities for level grinding, while ''Conquest'' focuses on the militaristic Nohr with more limited resources. The downloadable version comes with ''neither'' campaign, and so lets you choose which one to download for free once you reach the decision point. Access to the other campaigns, including a post-release [[TakeAThirdOption third option]] campaign called ''Revelation'', is restricted to DLC. Only the LimitedSpecialCollectorsUltimateEdition offers all three campaigns without further payments required. This has caused mixed reactions among non-Japanese gamers, especially when the edition with all the content ended up being shipped out in very limited numbers, many of which were snapped up by scalpers. Downplayed thanks to the fact that after the sixth chapter the campaigns are very different in terms of story, with a mostly different cast of characters and different stages to play in, and the fact that each other campaign can be purchased as DLC at half the price, effectively turning them into expansion packs. Due to their differences in resources and ability to grind, each campaign also works as a separate difficulty setting.

* ''Franchise/{{Pokemon}}'' is the TropeCodifier, with each version having exclusive Pokémon or certain ones with differing rarities. Other aspects are occasionally played with, though: the major examples being the main installments of [[VideoGame/PokemonRubyAndSapphire Gen III]] have the antagonists differ between the games[[note]]''Ruby'' and ''OMega has Team Magma attempting to increase the planet's landmass, while ''Sapphire'' has Team Aqua desiring to increase the size of the oceans. ''[[UpdatedRerelease Emerald]]'' has both villain teams in play, actively fighting each other and the player character in order to reach their respective goals.[[/note]] and [[VideoGame/PokemonBlackAndWhite Gen V]] having a differing final town and Gym Leader, in addition to each version having their own exclusive locations. Regardless, from [[VideoGame/PokemonDiamondAndPearl Gen IV]] onward, the series has had the ability to trade over Wi-Fi via the "Global Trade System", allowing a player to collect all the Pokémon without knowing someone with the other version personally or buying it yourself. The system initially had the annoying limitation of only allowing the player to search for Pokémon they already have registered as "seen" in their Pokédex; later games would allow you to simply type in the name even if you haven't seen them yet on that file.

* ''VideoGame/{{Robopon}}'' did this, though the first set of games had only one released in the US.

* The original release of ''VideoGame/YokaiWatch'' only came as one edition, but ''Yo-Kai Watch 2'' learned from Pokémon's success and was first released as ''Ganso'' and ''Honke'' (''Bony Spirits'' and ''Fleshy Souls'' in the US) which had exclusive {{Mons}}, and then ''Shin'uchi'' (''Psychic Specters''), which at least gave a NewGamePlus option for people who already cleared one of the first two versions. The same goes for the ''Yo-Kai Watch Blasters'' spinoff (which was split into ''Red Cat Corps'' and ''White Dog Squad'' versions, a third ''Moon Rabbit Crew'' version was added later but as a free update for the first two), ''Yo-Kai Watch 3'' (''Sushi'', ''Tempura'', and later ''Sukiyaki''), and ''Yo-Kai Watch Blasters 2'' (''Sword'' and ''Magnum''). In the case of ''Yo-kai Watch 3'' though, the International version instead combined all three games into one, averting this. ''Yo-kai Watch 4'' also plans to avert this, planning a single version for Nintendo Switch.

* Strangely, the Japanese DVD releases of ''Anime/SuzysZooDaisukiWitzy'' is hit by this - the first season is released across two volumes. The US release, however, combined both volumes into a single disc.

* ''Franchise/{{Pokemon}}'' is the TropeCodifier, with each version having exclusive Pokémon or certain ones with differing rarities. Other aspects are occasionally played with, though: the major examples being the main installments of [[VideoGame/PokemonRubyAndSapphire Gen III]] have the antagonists differ between the games[[note]]''Ruby'' has Team Magma attempting to increase the planet's landmass, while ''Sapphire'' has Team Aqua desiring to increase the size of the oceans. ''[[UpdatedRerelease Emerald]]'' has both villain teams in play, actively fighting each other and the player character in order to reach their respective goals.[[/note]] and [[VideoGame/PokemonBlackAndWhite Gen V]] having a differing final town and Gym Leader, in addition to each version having their own exclusive locations. Regardless, from [[VideoGame/PokemonDiamondAndPearl Gen IV]] onward, the series has had the ability to trade over Wi-Fi via the "Global Trade System", allowing a player to collect all the Pokémon without knowing someone with the other version personally or buying it yourself. The system initially had the annoying limitation of only allowing the player to search for Pokémon they already have registered as "seen" in their Pokédex; later games would allow you to simply type in the name even if you haven't seen them yet on that file.

*** ''Pokémon Yellow'' lacked Pokémon you could only get in ''Red'' AND only in ''Blue'', so if you bought ''Pokémon Yellow'', you also needed to trade with BOTH ''[[VideoGame/PokemonRedAndBlue Red and Blue]]'' to get certain Pokémon. The release of ''VideoGame/PokemonGoldAndSilver'' alleviated this somewhat with use of the Time Capsule; ''Silver'' and ''Crystal'' both have all the Pokémon that can't be found in Yellow, and also make it easier to obtain multiple Eevee and the other Tyrogue evolution, meaning if you can trade with one of those, you only need another RBY player for the fossil you didn't pick. You still need two other games, but it's not limited to only ''Red'' and ''Blue''. ''Pokémon Emerald'' also pulls the same trick.
*** Of course, this was offset by giving you access to the three starters without trading and some overall updates. So you were basically sacrificing easier 100% Completion for a better gameplay experience. ''Emerald'' lacks that trade-off, though.