Between Pokémon Red, Blue and Yellow
- Pokémon will have at least 3 max IVs
- The Pokémon’s Nature will be random
- The Pokémon’s Hidden Ability has a chance of being transferred
- Pokémon transferred from Red, Blue or Yellow will have a unique GameBoy mark
Between Pokémon X, Y, Alpha Sapphire, Omega Ruby, Sun and Moon
In addition to transferring between Red, Blue and Yellow, there will also be changes to how Pokémon Bank works.
- The National Pokédex will sync up between the games you use with Pokémon Bank
- All Pokémon you have seen/caught in your games will be combined and registered
- Pokémon Bank will now list the games you have each of your Pokémon in
- Pokémon do not need to be in Bank for them to register in your National Pokédex
- Battle Points can be sent between Pokémon Bank and your game
- Pokémon Bank will track a variety of stats from your games, cross referencing between all 6 games
Find the original press release here.