Generation I
Generation I (Japanese: 第一(だいいち)世代(せだい), Hepburn: Dai Ichi-sedai) (sometimes referred to as the Color Generation by older fans, due to the names of the versions released) are the first installments of the Pokémon franchise. Primarily released on the original Game Boy, the games begin with Pocket Monsters Red and Pocket Monsters Green in Japan in February 27, 1996, which are later joined with a third version Pocket Monsters Blue later in the same year and a special edition Pokémon Yellow Special Pikachu Edition in 1998, Internationally, the first two games were released as Pokémon Red Version and Pokémon Blue Version in September 1998, using the code, script and artwork of the Japanese Blue, instead of the initial Red and Green (except for wild Pokémon encounters). Later, they were followed by the same Pokémon Yellow as in Japan. While the mainline games were released on the Game Boy, a few spin-off titles such as Pokémon Stadium, Hey You, Pikachu!, Pokémon Snap, and Pokémon Puzzle League were made for the Nintendo 64 in Japan and the United States. These games featured the initial 151 Pokémon starting with Bulbasaur and ending with Mew.
Although rather basic by today's standards and in comparison to later titles, as this Generation marks the grand debut of the long-running Pokémon games and sets the standard for all future Generations, it is responsible for the series' revolutionary success into what become a multi-billiondollar franchise and one of Nintendo's flagship series alongside Super Mario and The Legend of Zelda.
Chronologically, all Generation I games take place around the same time as Generation III. Generation II takes place three years later.
Pokémon Red Version and Pokémon Blue Version would receive a remake in Generation III for the Game Boy Advance in 2004, Pokémon FireRed Version and Pokémon LeafGreen Version, while Yellow would later have its own in Generation VII through Pokémon: Let's Go, Pikachu! and Pokémon: Let's Go, Eevee! for the Nintendo Switch in 2018, two decades after the original's release.
Gameplay[]

Gameplay screenshot of Pokémon Red Version and Pokémon Blue Version played on the Game Boy
The gameplay primarily consists of the player trying to obtain all 151 Pokémon, defeating all the Gym Leaders, the Elite Four, and the Pokémon Champion while encountering other Pokémon Trainers along the way.
To find and catch a Pokémon, the player, who is a Pokémon Trainer, walks around in tall grass (or caves or uses the Hidden Move surf on water). When a wild Pokémon appears, the player battles it with a previously caught Pokémon to lower its health. Lowering the Pokémon's health weakens it, allowing the Trainer to capture it with a Poké Ball. The player is limited to carrying only six Pokémon at a time. Once the player catches a seventh Pokémon, it automatically transfers to a Pokémon Storage System. Players can change the six Pokémon in their lineup by accessing the Pokémon storage system, which contains 12 "boxes" that each hold 20 Pokémon (240 Pokémon in total).
Each Pokémon has its own stats, which consist of Attack, Defense, Speed, Special, and HP. These stats increase when the Pokémon gains a level. The lowest level a Pokémon can be is level 1, while the highest is level 100. Pokémon also have moves, which can be used to attack another Pokémon or to heal oneself. In total, there are 165 moves in Generation I, though a Pokémon can only have four moves and will have to forget a move to learn a new one.
Pokémon also come in different elemental types. There are 15 different elemental types of Pokémon, consisting of Bug, Dragon, Electric, Fighting, Fire, Flying, Ghost, Grass, Ground, Ice, Normal, Poison, Psychic, Rock, and Water. Each element has its own weakness, such as Fire Pokémon being weak against Water Pokémon, as well as its own strength, such as Water Pokémon being strong against Fire Pokémon. Pokémon receive less damage from and deal more damage to elements they are strong against, while on the other hand dealing less damage to and taking more damage from elements they are weak against. Elemental strengths and weaknesses encourage the player to keep a diverse selection of Pokémon to counter various types of enemy Pokémon effectively.
Some Pokémon can evolve into another Pokémon. This can happen when they reach a certain level, are traded with another character or player, or are given an evolutionary stone. When a Pokémon evolves, they develop better stats and may also change types.
The player must travel across Kanto and defeat the eight Gym Leaders at their Gyms, earning a Badge corresponding with that Gym. Each Gym specializes in a type of Pokémon, resulting in certain types of Pokémon being effective in certain gyms, while other types of Pokémon are weak in certain gyms. After defeating the eight Gym Leaders, the player progresses to the Elite Four, where he/she fights the four best trainers in the entire region. After defeating them, the player must then defeat the Pokémon Champion, which will result in the player becoming the new Pokémon Champion, completing the game.
Players can also trade Pokémon with or fight against other players through a Game Link Cable. Some Pokémon have to be traded so that they can evolve.
First partner Pokémon[]
The player can choose one of three First partner Pokémon at the beginning of the game. The choices are: Bulbasaur (Grass), Charmander (Fire), and Squirtle (Water).
However, in Pokémon Yellow Special Pikachu Edition, the player had only Pikachu to choose as a starter, while the Rival (Blue) always chooses Eevee (although the opposite was intended to happen according to Professor Oak), which evolves into either Vaporeon, Jolteon or Flareon depending on the results in the battles with him at Prof. Oak's lab and at Route 22.
Gym Leaders, Elite Four and Champion[]
Generation I introduced a unique set of Gym Leaders and the Elite Four. All of these trainers specialized in a specific type of Pokémon and are key to progressing through the game. They all reappear in Generation II's and Pokémon HeartGold Version and Pokémon SoulSilver Version, except for Koga, who is replaced by Janine, and Giovanni, who is replaced by Blue in Gold, Silver, Crystal, HeartGold, and SoulSilver.
Gym Leaders[]
Leader Name | Type | HM usable after defeat |
Place |
---|---|---|---|
Brock | Rock | Flash | Pewter City |
Misty | Water | Cut | Cerulean City |
Lt. Surge | Electric | Fly | Vermilion City |
Erika | Grass | Strength | Celadon City |
Koga | Poison | Surf | Fuchsia City |
Sabrina | Psychic | N/A | Saffron City |
Blaine | Fire | N/A | Cinnabar City |
Giovanni | Ground | N/A | Viridian City |
Elite Four[]
Member | Type |
---|---|
Lorelei | Ice |
Bruno | Fighting |
Agatha | Ghost |
Lance | Dragon |
Pokémon Champion[]
Member | Type |
---|---|
Blue | ??? |
Pokémon[]
Games[]
Main series[]
Side series[]
Trivia[]

The original Pokémon battle sprites of the initial games prior to Yellow are poorly created
- The Generation I games are the Game Boy's best-selling standalone game, selling over 46 million worldwide. It is also the best-selling RPG genre game of all-time.
- Since the development of the original games began as early as 1990, this would make Generation I by far the longest time it took to release its games.
- Pokémon Green, the second game of the initial pair of the Japanese release, was never released internationally. This has caused many fans overseas to collect this version much more often than that region's Red. In fact, this version overshadowed its counterpart enough that most veteran players believe Green is the first true Pokémon game even though Red is technically first in line.
- Despite the international version of Pokémon Yellow Special Pikachu Edition have its box saying it is for the Game Boy, it is actually for the Game Boy Color. This is because the Japanese version was released a week before that handheld's release in that region and therefore on the original Game Boy.
- If one plays Red, Green, or Blue on the Game Boy Color, Game Boy Advance, or Game Boy Player (on GameCube), the stars on the Game Freak logo as well as the game itself will be colored differently depending on the version of the game. However, as with most other original Game Boy games, this is because the GBC has a preset memory using a very limited palette of two colors. The original grayscale can be restored by pressing Left + B on the Game Boy startup screen.
- If the aforementioned games are played on the Super Game Boy, an add-on for the Super Nintendo Entertainment System to make Game Boy games able to be played on the 16-bit home console, they will become fully colored.
- Due to the limitations of the Game Boy and troubled development, the original Japanese Red & Green is infamous for having many game-breaking bugs and Pokémon sprites being unlike the official artwork. In the International Red & Blue release, most were slightly corrected but still appear imperfect, alongside fixing a few bugs. Yellow has the front sprites look much like the artwork, but the back ones remain completely unchanged from Red & Green, while having further corrections. All Pokémon would have their proper appearances in Generation II.
- It was originally intended that the player could battle Professor Oak after beating the Champion, but it was not included in the final games. There is however, a glitch that can be activated to battle him.
- Unlike all subsequent Generations, Generation I is known for having many balance issues during battle due to the limited memory and movesets of Pokémon. For example, the Special stat represents both Special Attack and Special Defense, and the Bag can only hold 20 items, forcing the player to frequently store unwanted items to the PC. Psychic-type Pokémon in this era are known to have virtually no weaknesses; Although the Ghost-type does exist, a bug makes their moves ineffective instead of super effective and most of such Pokémon are part-Poison-type.
- Although Mew cannot be obtained under normal circumstances, there is a well-known glitch known as the "Mew Glitch" that enables players to encounter and catch the Mythical Pokémon.
- Pokémon Red, Green, Blue and Yellow (Japanese)/ Pokémon Red, Blue and Yellow (International) are the first main series games to be released on the Nintendo Virtual Console.
- Generation I is the only generation where you cannot get a level 1 Pokémon, unless you have a Generation II game.
- This remains the only Generation where the games don't have a Legendary Pokémon on the games' box art but instead the First partner Pokémon in their full evolution state except for Pikachu in the case of Pokémon Yellow Special Pikachu Edition. This would repeat in Pokémon: Let's Go, Pikachu! and Pokémon: Let's Go, Eevee!.
- Since the main games of this Generation each took up a lot of space on a Game Boy cartridge, Game Freak had to make a decision between allowing 3 save files or Pokémon nicknames. In the end, they chose nicknames over save files.