List of Promotional Event Pokémon
Nintendo Event Pokémon usually have a specific ID No. and original trainer ID and are holding a special item; however sometimes a player might get an item, such as a ticket for a ship cruise to an odd island, to catch it on their own as in the case of Deoxys.
Pokemon Obtainable By Item
The following are some nintendo event pokemon obtainable via a special rare item.
Latias or Latios
In Emerald which event dragon (Latias or Latios) they didn't choose or couldn't get at all, they could get in Southern Island. In Ruby and Sapphire, players could use an e-reader to get the Eon Ticket to get the other dragon or trade it to Emerald to catch the other one holding a rare Soul Dew.
Lugia and Ho-Oh
In Emerald or FireRed and LeafGreen, players could get the Mystic Ticket which would take them to Navel Rock. In Navel Rock, players could capture a Level 70 Ho-Oh upstairs, and a Level 70 Lugia downstairs. If the player used the itemfinder where Ho-Oh was standing or landed, they would get the item Sacred Ash for Ho-Oh to hold.
Deoxys
In Emerald or FireRed and LeafGreen, the Aurora Ticket was possible to obtain to go to Birth Island and capture a Level 30 Deoxys. This is currently the only way to capture a legit one by hand. Before getting to battle Deoxys, however, players had to solve a simple, small puzzle envolving a magical triangle.
Mew
Mew was only able to be caught in Emerald by using the Old Sea Chart to get to Water's Edge Island. There a Level 30 Mew will be floating. Mew will get shocked and run in the grass to make the player find it own their own.
Manaphy in Pokemon Ranger
Manaphy was able to not catch, but to get an egg of. In Pokemon Ranger, once beating the game players would be able to play a special mission by inputting a code found on Manaphy.com. Once beaten, players could transfer the egg to their copy of Diamond or Pearl. Once it was obtained in Diamond or Pearl, players could breed it to get the Manaphy's offspring, Phione. Phione, however, dose not evolve to Manaphy.