theSLAYER

In the game Pokémon Emerald, after the player defeats the Elite For, the Marine Cave randomly appears on Route 105, Route 125, Route 127 or Route 129.
The Weather Institute on Route 119 will inform the player where the heavy rainfall has been observed.

In the game Pokémon Emerald, after the player defeats the Elite For, the Terra Cave randomly appears on Route 114, Route 115, Route 116 or Route 118.
The Weather Institute on Route 119 will inform the player where the harsh sunlight has been observed.

In the game Pokémon Emerald, a Sudowoodo is masquerading as a tree in the Battle Frontier.
Using a Wailmer Pail will cause it to battle the player.

In the game Pokémon Ruby, Groudon can be met in the Cave of Origin as part of the story narrative.

In the game Pokémon Sapphire, Kyogre can be met in the Cave of Origin as part of the story narrative.

In the games Pokémon Ruby & Sapphire, Rayquaza can be caught in the Sky Pillar during the post-game.

In the game Pokémon Emerald, Rayquaza can be captured right after the Groudon VS Kyogre battle,
which in this instance it can be encountered right before the player defeats the Elite Four.

This event was given away to commemorate The Year of Legendary Pokémon via Serial code for US 3DS, and Nintendo Network for EU 3DS.
The gift received between Pokémon Sun & Moon and Pokémon Ultra Sun & Ultra Moon will slightly differ, in areas such as held item, level and moveset.

This gift can only received on Pokémon Sun & Ultra Sun, while it is normally encountered at the Ultra Space Wilds of Pokémon Ultra Moon.
US Serial Codes in North America were distributed via Target stores, between Oct 19 to Oct 28, 2018.
US Serial Code in Spain were distributed via various participating shops, between Oct 12 to Oct 31, 2018.
US Serial Codes via Trainer Club Newsletter start from Oct 10, 2018.
EU Nintendo Network distribution for EU region were done between Oct 05 to Oct 21, 2018.
     Species   Zekrom   Nickname   (default, save lang)   OT   2018 Legends   TID   100518  Distribution   (Various)   Location   a lovely place   Dates   (Various)   PID   Cannot Be Shiny   Games   US & EU 3DS: S                                                                Lv. 60    Nature   Random   Ability   Teravolt (1)   Item   None   Bundled Item   None   Card Per Save   Only One Allowed    Moves   (ITALIC means Relearnable)   Slash   Zen Headbutt   Fusion Bolt   Dragon Claw   WC ID 655: 「Shocking Zekrom!」's receiving text 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center.

Classic Shocking Zekrom! The Deep Black Legendary Pokémon
Zekrom enters the battlefield with its
dark presence, then rains down
a series of devastating attacks. Format Ver.1.0.6-3, Post Updated Date:20181005_0147
     Species   Zekrom   Nickname   (default, save lang)   OT   2018 Legends   TID   100518  Distribution   (Various)   Location   a lovely place   Dates   (Various)   PID   Cannot Be Shiny   Games   US & EU 3DS: US                                                                Lv. 100    Nature   Random   Ability   Teravolt (1)   Item   Gold Bottle Cap   Bundled Item   None   Card Per Save   Only One Allowed    Moves   (ITALIC means Relearnable)   Fusion Bolt   Bolt Strike   Outrage   Stone Edge   WC ID 655: 「Shocking Zekrom!」's receiving text 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center.

Classic Shocking Zekrom! The Deep Black Legendary Pokémon
Zekrom enters the battlefield with its
dark presence, then rains down
a series of devastating attacks. Format Ver.1.0.6-3, Post Updated Date:20181005_0147

This event was given away to commemorate The Year of Legendary Pokémon via Serial code for US 3DS, and Nintendo Network for EU 3DS.
The gift received between Pokémon Sun & Moon and Pokémon Ultra Sun & Ultra Moon will slightly differ, in areas such as held item, level and moveset.

This gift can only received on Pokémon Moon & Ultra Moon, while it is normally encountered at the Ultra Space Wilds of Pokémon Ultra Sun.
US Serial Codes in North America were distributed via Target stores, between Oct 19 to Oct 28, 2018.
US Serial Code in Spain were distributed via various participating shops, between Oct 12 to Oct 31, 2018.
US Serial Codes via Trainer Club Newsletter start from Oct 10, 2018.
EU Nintendo Network distribution for EU region were done between Oct 05 to Oct 21, 2018.
     Species   Reshiram   Nickname   (default, save lang)   OT   2018 Legends   TID   100518   Distribution   (Various)   Location   a lovely place   Dates   (Various)   PID   Cannot Be Shiny   Games   US & EU 3DS: M                                                                Lv. 60    Nature   Random   Ability   Turboblaze (1)   Item   None   Bundled Item   None   Card Per Save   Only One Allowed    Moves   (ITALIC means Relearnable)   Slash   Extrasensory   Fusion Flare   Dragon Pulse   WC ID 655: 「Scorching Reshiram!」's receiving text 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center.

Classic Scorching Reshiram! The Vast White Legendary Pokémon
Reshiram heats up battles with a quartet
of awesome moves that will strike hard
against any foe. Format Ver.1.0.6-3, Post Updated Date:20181005_0143
     Species   Reshiram   Nickname   (default, save lang)   OT   2018 Legends   TID   100518  Distribution   (Various)   Location   a lovely place   Dates   (Various)   PID   Cannot Be Shiny   Games   US & EU 3DS: UM                                                                Lv. 100    Nature   Random   Ability   Turboblaze (1)   Item   Gold Bottle Cap   Bundled Item   None   Card Per Save   Only One Allowed    Moves   (ITALIC means Relearnable)   Fusion Flare   Blue Flare   Draco Meteor   Earth Power   WC ID 655: 「Scorching Reshiram!」's receiving text 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center.

Classic Scorching Reshiram! The Vast White Legendary Pokémon
Reshiram heats up battles with a quartet
of awesome moves that will strike hard
against any foe. Format Ver.1.0.6-3, Post Updated Date:20181005_0144

In the games Pokémon FireRed & LeafGreen, a pair of Snorlax will stop the player from being able to reach Fuchsia City,
until the player gains possession of the key item Poké Flute, that is able to awaken sleeping Pokémon.

In the games Pokémon FireRed & LeafGreen, a terrified Silph Co. employee will give the player a Lapras, as thanks for saving Silph Co. from Team Rocket.

In the games Pokémon FireRed & LeafGreen, part of the side-quest in Sevii Islands requires the player to find Lostelle,
who apparently wandered too far into the Berry Forest, and is now pestered by a Hypno.

In the game Pokémon FireRed & LeafGreen, Mewtwo can be encountered in the Cerulean Cave after players complete the Sevii Island's quest that involves the delivery of the key item Sapphire to Celio.
The Sevee Island quest can only be done after the player defeats the Elite Four, and obtains the National Dex
(which involves having 60 species registered in the Kanto Dex).

In the game Pokémon Ruby, Latios roams Hoenn after the player's first entry into the Hall of Fame and watches the TV broadcast in the player's living room.

In the game Pokémon Emerald, the same conditions as above apply, with an additional condition:
the player must choose Blue after watching the TV broadcast.
Because of the Roamers IV Glitch, roamers in Gen III will have weak IVs (besides Hit Points).
As a result, the Hidden Power of roamer will always be Fighting Type.
Pokémon Emerald isn't affected by the glitch, however.

In the game Pokémon Sapphire, Latias roams Hoenn after the player's first entry into the Hall of Fame and watches the TV broadcast in the player's living room.

In the game Pokémon Emerald, the same conditions as above apply, with an additional condition:
the player must choose Red after watching the TV broadcast.
Because of the Roamers IV Glitch, roamers in Gen III will have weak IVs (besides Hit Points).
As a result, the Hidden Power of roamer will always be Fighting Type.
Pokémon Emerald isn't affected by the glitch, however.

In the games Pokémon FireRed & LeafGreen, after the player delivers the key item Sapphire to Celio,
and if the player chose Charmander as their starter, Suicune will begin roaming throughout Kanto.
Because of the Roamers IV Glitch, roamers in Gen III will have weak IVs (besides Hit Points).
As a result, the Hidden Power of roamer will always be Fighting Type.
 

In the games Pokémon FireRed & LeafGreen, after the player delivers the key item Sapphire to Celio,
and if the player chose Bulbasaur as their starter, Entei will begin roaming throughout Kanto.
Because of the Roamers IV Glitch, roamers in Gen III will have weak IVs (besides Hit Points).
As a result, the Hidden Power of roamer will always be Fighting Type.

In the games Pokémon FireRed & LeafGreen, after the player delivers the key item Sapphire to Celio,
and if the player chose Squirtle as their starter, Raikou will begin roaming throughout Kanto.
Because of the Roamers IV Glitch, roamers in Gen III will have weak IVs (besides Hit Points).
As a result, the Hidden Power of roamer will always be Fighting Type.

This page hosts the starter Eevee obtained during the narrative of Pokémon XD: Gale of Darkness.
The PID of the Eevee is determined a few frames after the determination of the TID and SID of the trainer, not unlike the starters in Colosseum (read more about that here; XD/Colo PID search can be done with this tool).
As a result, not every TID/SID and PID combo will be legitimately shiny.
More Colosseum and XD Pokémon can be found at this page.

In the games Pokémon Diamond, Pearl & Platinum, the player obtains an egg from Riley after they reach the end of Iron Island together.
As per any egg gift, it has a chance of being shiny when traded to another trainer with the correct TID/SID combo.

In the games Pokémon Diamond & Pearl, the player obtains an egg when the player interacts with the Hiker near the gate to the right of Hearthome City.
As per any egg gift, it has a chance of being shiny when traded to another trainer with the correct TID/SID combo.

In the games Pokémon HeartGold & SoulSilver, when the player interacts with Primo in the Violet City's Pokémon Center,
and gives the correct passwords, Primo will give the player an egg.

Officially, the passwords were only given for Japanese players via the Daisuki Club
(which the service for the passwords has since been defunct).
However, players can use external codeword generator to unlock the exclusive content.
As per any egg gift, it has a chance of being shiny when traded to another trainer with the correct TID/SID combo.

In the games Pokémon HeartGold & SoulSilver, when the player interacts with Primo in the Violet City's Pokémon Center,
and gives the correct passwords, Primo will give the player an egg.

Officially, the passwords were only given for Japanese players via the Daisuki Club
(which the service for the passwords has since been defunct).
However, players can use external codeword generator to unlock the exclusive content.
As per any egg gift, it has a chance of being shiny when traded to another trainer with the correct TID/SID combo.

In the games Pokémon HeartGold & SoulSilver, when the player interacts with Primo in the Violet City's Pokémon Center,
and gives the correct passwords, Primo will give the player an egg.

Officially, the passwords were only given for Japanese players via the Daisuki Club
(which the service for the passwords has since been defunct).
However, players can use external codeword generator to unlock the exclusive content.
As per any egg gift, it has a chance of being shiny when traded to another trainer with the correct TID/SID combo.

This page hosts the shadow and purified versions of the Shadow Absol obtained during the narrative of Pokémon Colosseum.
More Colosseum and XD Pokémon can be found at this page.

This page hosts the shadow and purified versions of the Shadow Vibrava obtained during the narrative of Pokémon Colosseum.
More Colosseum and XD Pokémon can be found at this page.