Legendary Pokémon

Legendary Pokémon are a type of very rare and powerful Pokémon. They are usually the subject of mythology and lore regarding the World of Pokémon, although every Legendary Pokémon is associated with a specific region. They have been around since the start of the Pokémon franchise. Legendary Pokémon are generally the most powerful type of Pokémon. Because of this, they are often the target of villain groups within the main Pokémon series and the anime, as they seek to control or change the world.

Pokémon series
In the main Pokémon series, each Legendary Pokémon is found only once in the game, aside from trading. Several of them are found in optional dungeons, but certain Pokémon such as Mew are Event Pokémon, which can only be obtained from real world promotional events and, by extension, trading with other players.

Generally, legendary Pokémon have a very low catch rate, making them more difficult to catch than Pokémon normally found in the wild. In most cases, a Master Ball is used to capture them. Legendary Pokémon cannot breed, as is possible with other Pokémon, and have a slow leveling rate. Most Legendary Pokémon are genderless.

Pokémon Red and Blue Versions / Pokémon Yellow Version
In Pokémon Red and Blue Versions and Pokémon Yellow Version, there are five Legendary Pokémon: Articuno, Zapdos, Moltres, Mewtwo, and one Event Pokémon, Mew.

Pokémon Gold and Silver Versions / Pokémon Crystal Version
Six more Legendary Pokémon were introduced in Pokémon Gold and Silver Versions, also included in Pokémon Crystal Version. The former two are the first games where a Legendary Pokémon serves as the Mascot Pokémon, setting a trend for all subsequent Pokémon titles; Ho-Oh is on the cover of Pokémon Gold Version, and Lugia is on the cover for Pokémon Silver Version. For Pokémon Crystal Version, Suicune appears on the front cover. There is also the time-traveling Celebi, guardian of the Ilex Forest, that was only available through an event.

Since Pokémon Gold and Silver Versions and Pokémon Crystal Version, the games have featured Legendary Pokémon that randomly move around the world map, after a certain event has been completed, and are randomly encountered. Once the player character has their entry in the Pokédex, their location can be tracked as usual. These Pokémon typically flee from battle, making them even harder to catch, although the moves Mean Look or Block can prevent them from fleeing. These Legendary Pokémon retain their HP level and status condition between battles.

Pokémon Ruby and Sapphire Versions / Pokémon Emerald Version
Ten Legendary Pokémon were introduced in Pokémon Ruby and Sapphire Versions, and would also appear in Pokémon Emerald Version. These are the first games to have Legendary Pokémon with a definitive domain: Kyogre has power over the sea, Groudon has power over the land, and Rayquaza has power over the sky. They also introduced the first Legendary Pokémon that have a gender and are gender-exclusive: Latias, who is always female, and Latios, who is always male. Also introduced were the three Regi's, Regirock, Regice, and Registeel. The games have two Event Pokémon: Jirachi and Deoxys.

Legendary Pokémon play a larger part in the storyline than in previous games. In Pokémon Sapphire Version, Team Aqua tries to use Kyogre to expand the oceans, and the player character teams up with Team Magma to try and stop them.

Pokémon FireRed and LeafGreen Versions
In Pokémon FireRed and LeafGreen Versions, the player character can try and obtain Suicune, Entei, and Raikou by defeating the Elite Four and their Rival, who is the Pokémon Champion.

Pokémon Diamond and Pearl Versions / Pokémon Platinum Version
In Pokémon Diamond and Pearl Versions, 13 Legendary Pokémon were introduced. A few of them have God-like powers, such as Dialga, who has power over time, and Palkia, who has power over space. An Event Legendary Pokémon, Arceus, is referred to as the creator of all Pokémon.

The games introduced the first Legendary Pokémon that is capable of breeding, Manaphy. It lays a Pokémon Egg containing Phione, although Phione is not the base form of Manaphy and therefore cannot evolve into it. The Pokétch is used to track Legendary Pokémon instead of the Pokédex.

Uxie, Mesprit, and Azelf each govern over intelligence, emotion, and willpower respectively, and are guardians of Sinnoh's three signature lakes. Heatran resides atop Stark Mountain, Regigigas is sealed inside the Snowpoint Temple and is the leader of the three Regis from the Generation III games, and Giratina resides in Turnback Cave. Cresselia is the embodiment of the crescent moon. There are three Event Pokémon: Darkrai (who is the opposite of Cresselia), Shaymin, and Arceus.

Pokémon Mystery Dungeon: Red Rescue Team and Blue Rescue Team
In Pokémon Mystery Dungeon: Red Rescue Team and Blue Rescue Team, the Legendary Pokémon are the only Pokémon types of which there is only one. Almost all of them have a large part in the storyline, especially Zapdos, Moltres, Articuno, Groudon and Rayquaza in the first part of the game.

In the Pokémon anime
In the Pokémon anime, legendary Pokémon are Pokémon which have been the subject of ancient legends. Such Pokémon are still often (but not always) unique and frequently very powerful. Legendary Pokémon in the anime are able to breed, meaning they do have genders (although some legendary Pokémon in the games also have genders, the majority do not and only two species can breed).

Legendaries are sometimes major creatures in their own right, often antagonists or out-of-control forces of nature. Mewtwo, in particular, is a recurring character, with a major role in Pokémon: The First Movie and its sequel, Mewtwo Returns. Unlike in the games, where catching a legendary Pokémon may be done by the protagonist to save the world, the exact opposite is true for the anime. In the anime (particularly in Pokémon: The Movie 2000), the capture of a legendary Pokémon would have deadly repercussions and is only ever attempted by human antagonists. To date, only Regice, Registeel and Regirock have been confirmed to have been captured by a trainer (Pyramid King Brandon). An Articuno did help Factory Head Noland battle Ash, but it had not actually been captured, just befriended.

Every Pokémon movie has centered around an encounter with one or more legendary Pokémon, often the first appearance of those Pokémon on screen. Subsequent anime episodes featuring those Pokémon are common. Excluding the fourth generation Pokémon, Raikou is the only legendary Pokémon which Ash has not seen or had some kind of connection with (although Raikou did have its own Pokémon Chronicles special and Misty's Togepi once encountered it).

Lucario and the Mystery of Mew
At first, Lucario was widely speculated to be a legendary, as its appearance in "Lucario and the Mystery of Mew" would seem to prove. However, Lucario are normally not considered legendary; the one belonging to Sir Aaron performed famous deeds that became a popular legend. This Lucario also appeared to be the most skillful at using Aura, and could perform telepathy, a characteristic mostly attributed to Legendaries, convincing many that it was a Legendary. When the third Gym Leader of Sinnoh, as well as Sinnoh's champion, had Lucario on their roster and Lucario was revealed to have a pre-evolved form, Lucario was seen as a normal Pokemon.

List of Legendary Pokémon
There are a total of 59 Legendary Pokémon.

Kanto

 * Articuno
 * Zapdos
 * Moltres
 * Mewtwo
 * Mew

Johto

 * Raikou
 * Entei
 * Suicune
 * Lugia
 * Ho-Oh
 * Celebi

Hoenn

 * Regirock
 * Regice
 * Registeel
 * Latias
 * Latios
 * Kyogre
 * Groudon
 * Rayquaza
 * Jirachi
 * Deoxys

Sinnoh

 * Uxie
 * Mesprit
 * Azelf
 * Dialga
 * Palkia
 * Heatran
 * Regigigas
 * Giratina
 * Cresselia
 * Phione
 * Manaphy
 * Darkrai
 * Shaymin
 * Arceus

Unova

 * Cobalion
 * Terrakion
 * Virizion
 * Tornadus
 * Thundurus
 * Reshiram
 * Zekrom
 * Landorus
 * Kyurem

Kalos

 * Xerneas
 * Yveltal
 * Zygarde

Alola

 * Type: Null
 * Silvally
 * Tapu Koko
 * Tapu Lele
 * Tapu Bulu
 * Tapu Fini
 * Cosmog
 * Cosmoem
 * Solgaleo
 * Lunala
 * Necrozma

Galar

 * Zacian
 * Zamazenta
 * Eternatus
 * Kubfu
 * Urshifu
 * Regieleki
 * Regidrago
 * Glastrier
 * Spectrier
 * Calyrex
 * Galarian Articuno
 * Galarian Zapdos
 * Galarian Moltres

Trivia

 * Although Arcanine is part of the "Legendary" category, it is not a Legendary Pokémon.