List of in-game event Pokémon in Generation III

This is a list of Pokémon obtainable from events found in the Generation III Pokémon games. These specific instances of Pokémon can only be obtained once per game; however, some may also be obtained in other ways as well.

Starter Pokémon
Professor Birch gets attacked by a wild or  and the undefined has to use either, , or  to save him.

Wynaut
The old woman by the sand baths in Lavaridge Town will give the undefined a.

Castform
The staff of the Weather Institute will give the player a for saving the facility from Team Magma or Team Aqua.

Kecleon
There are eight set encounters with Kecleon accessible via the Devon Scope throughout  and.

Fossil Pokémon
In Ruby and Sapphire, the player may choose between the Root and Claw Fossils on, while the other fossil will sink forever. In Emerald, the player may choose between the two fossils in the Mirage Tower, while the other fossil will be available to him/her after defeating the Elite Four in the Desert Underpass. The fossils can be revived at the Devon Corporation headquarters in Rustboro City.

Beldum
After defeating the Elite Four, will leave a  at his cottage in Mossdeep City.

Rayquaza
is found on the roof of the Sky Pillar, which reveals itself after the player defeats the Elite Four. In Emerald, is found on the roof of the Sky Pillar, where it sleeps after quelling the fight between  and. It can be challenged as soon as the events in Sootopolis City are resolved.

Legendary titans
The caves where the titans can be caught can be accessed only after visiting the rear of the Sealed Chamber with a in the lead spot of the party and a  in the last spot. In Emerald, the player must have a in the lead spot of the party and a  in the last spot.

Regirock
To solve the puzzle leading to in the Desert Ruins, the player must read the Braille inscription in the rear of the lobby, then go two steps right, then two steps down, and then use. In Emerald, the player must read the Braille inscription in the rear of the lobby, then go two steps left, then two steps down, and then use.

Regice
To solve the puzzle leading to in the Island Cave, the player must read the Braille inscription in the rear of the lobby, then wait two minutes without moving. In Emerald, the player must read the Braille inscription in the rear of the lobby, then must make a counterclockwise lap of the chamber, sticking close to the walls.

Registeel
To solve the puzzle leading to in the Ancient Tomb, the player must read the Braille inscription in the rear of the lobby, then attempt to use  in the center of the room. In Emerald, the player must read the Braille inscription in the rear of the lobby, then attempt to use in the center of the room.

Latias
In Ruby, Latias can be found on Southern Island, which can be accessed with the Eon Ticket. In Sapphire, Latias will roam Hoenn after the player learns of her on a news broadcast after beating the Elite Four. In Emerald, after beating the Elite Four, the undefined will see a news broadcast about a Pokémon roaming Hoenn. The player's will then ask what color the Pokémon was. If the player answers "Red", Latias will be the Roaming Pokémon. If the player answers "Blue", Latias will be found on Southern Island.

Latios
In Sapphire, Latios can be found on Southern Island, which can be accessed with the Eon Ticket. In Ruby, Latios will roam Hoenn after the player learns of him on a news broadcast after beating the Elite Four. In Emerald, after beating the Elite Four, the undefined will see a news broadcast about a Pokémon roaming Hoenn. The player's will then ask what color the Pokémon was. If the player answers "Blue", Latios will be the Roaming Pokémon. If the player answers "Red", Latios will be found on Southern Island.

Groudon
is Ruby. It is found during the climax of the game, in the Cave of Origin.

Kyogre
is Sapphire. It is found during the climax of the game, in the Cave of Origin.

Johto Starters
Professor Birch will give the player either, , or after completing the regional Pokédex.

Sudowoodo
is located in the southeast section of the. Much like in Generation II games, NPCs will talk about it as a tree. However, when the player uses the Wailmer Pail on it, it will spring to life.

Groudon
After defeating the Elite Four, a researcher inside the Weather Institute will occasionally tell the undefined about harsh sunlight on either Route, , , or. At the specified route, he or she will discover a newly formed cave - the Terra Cave, where has been resting since its battle with.

Kyogre
After defeating the Elite Four, a researcher inside the Weather Institute will occasionally tell the undefined about torrential rainfall on either Route, , , or. If the player s in a newly created trench of deep water, he or she will discover the Marine Cave, where has been resting since its battle with.

Mew
If the undefined has an Old Sea Map, he or she can take a ferry to Faraway Island. Here, the player can catch. The Old Sea Map was only ever distributed in Japan, so the event remains Japanese-exclusive.

Starter Pokémon
Professor Oak gives the undefined a choice of, , or as starter Pokémon.

Magikarp
A salesman in 's Pokémon Center will offer a to the player for 500.

Eevee
A Poké Ball containing can be found on the roof floor of Celadon Mansion in Celadon City.

Snorlax
There are two set encounters with Snorlax accessible via the Poké Flute; one on and one on. The player must capture or defeat at least one of them to proceed to Fuchsia City.

Hitmonlee and Hitmonchan
Koichi, the master of the Fighting Dojo in Saffron City, will reward the undefined with their choice of either or  after defeating him.

Lapras
After defeating during Team Rocket's invasion of Silph Co., an onlooking Silph employee will entrust the player with a.

Hypno
At Berry Forest, a wild Hypno was found attacking Lostelle. The player must either catch or defeat it in order for Lostelle to go home.

Omanyte and Kabuto
The Helix and Dome Fossils are found at the end of Mt. Moon, but the player may only choose one to keep. The player may revive the Fossil in the Pokémon Lab on Cinnabar Island.

Aerodactyl
The Old Amber is located in the secret part of the Pewter Museum of Science, which can only be accessed with. The player may revive the Fossil in the Pokémon Lab on Cinnabar Island.

Togepi
A at the end of the Water Labyrinth will give the player a  Egg if there is a party slot available. If the player shows Togepi to the Gentleman when its friendship is high, but before it evolves, he will mention Daisy, helping complete her entry in the Fame Checker.

Articuno
is found within the depths of the Seafoam Islands.

Zapdos
is found inside the abandoned Power Plant.

Moltres
, as opposed to being found inside in Generation I, is found on the peak of Mt. Ember of the Sevii Islands.

Mewtwo
is found within the depths of Cerulean Cave, accessible only to powerful s who have defeated the Elite Four.

Legendary beasts
After the undefined defeats Team Rocket in the Rocket Warehouse on Five Island, one of the legendary beasts of Johto will start Kanto. The beast that appears varies based on what Pokémon the player chose as his or her. In the case of and, the player should be wary of the ; if the beast uses Roar to flee from battle, it will permanently disappear.

Entei
If the undefined chose :

Suicune
If the undefined chose :

Raikou
If the undefined chose :

Lugia and Ho-Oh
If the undefined has a, he or she can take a ferry to Navel Rock. Here, the player can catch in its depths, and  at its peak.

Deoxys
If the undefined has an, he or she can take a ferry to Birth Island. is always in its in FireRed,  in LeafGreen and  in.

Starter Pokémon
Espeon and Umbreon are in the player's possession at the beginning of the game.

Plusle
Plusle is given to the player by Duking after rescuing it.

Starter Pokémon
This Eevee is in the player's possession from the beginning of the game.

Johto starter Pokémon
After completing Mt. Battle by defeating 100 opponents with the same party, the player can have one of the following Johto starters. The player is able to redo the challenge all over again and obtain the remaining Pokémon that were not chosen.