Find out how to obtain your pass to Southern Island!
http://www.nintendoworldreport.com/news/38930/eon-ticket-information-announced-for-both-us-and-uk
Using Streetpass will enable you to obtain the Eon Ticket, according to both the US and UK Pokémon branches.
For the UK, the Eon Ticket will be distributed via Streetpass to those who go to the London launch event on November 29. Those who obtain the Eon Ticket will be able to distribute it to those who did not attend the event by simply exchanging Streetpass information with that person. For the US, the Eon Ticket will be distributed to those who attend the many Pokémon League events held across the United States, which will also enable them to distribute tickets to those who did not attend.
The Eon Ticket will enable those who obtain it to travel to Southern Island in Pokémon Omega Ruby and Alpha Sapphire, where they can capture Latios or Latias, depending on the version of the game.