Omega Ruby and Alpha Sapphire were originally released in 2014 for the Nintendo 3DS. They are remakes of Ruby and Sapphire. The original cartridges and digital downloads are able to trade and battle with each other, and with the 3DS games X and Y, using the wireless capabilities of the 3DS.
Using the Pokémon Bank application for the 3DS, Pokémon from previous games can be transferred into Omega Ruby and Alpha Sapphire. Specifically, any Pokémon contained in Black, White, Black 2, or White 2 can be sent from that game into Pokémon Bank with the Poké Transporter application, from where it can be moved into Omega Ruby and Alpha Sapphire. Pokémon can be sent into Black, White, Black 2, and White 2 from Ruby, Sapphire, & Emerald, FireRed & LeafGreen, Colosseum, XD: Gale of Darkness, Diamond, Pearl, & Platinum, and HeartGold & SoulSilver, meaning any Pokémon originating in one of these games can be ultimately transferred into Omega Ruby or Alpha Sapphire.
Pokémon can also be moved from Omega Ruby and Alpha Sapphire into Pokémon Bank, from where they can be moved into Sun, Moon, Ultra Sun, or Ultra Moon, or moved into the Switch application Pokémon HOME, from where they can be accessed by Nintendo Switch games with which they are compatible.
The first 721 Pokémon in the National Pokédex are all programmed into the game. Between the two games, the player can access 211 Pokémon that are part of the Hoenn Dex. Many Pokémon from other generations can be obtained late in the game and after defeating the Elite Four. Pokémon that are missing from these games can be traded in from X or Y, or transferred from any previous Game Boy Advance, GameCube, or Nintendo DS game.
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