Latias and Latios Factor
Either Latias or Latios can be found randomly in the wild after defeating the Elite Four. After the credits roll and you're in your room, go downstairs and watch the broadcast on TV. Latias or Latios will then appear in the wild randomly depending upon the following factors:
Factors
If you're playing Ruby, Latios will appear in the wild.
If you're playing Sapphire, Latias will appear in the wild.
If you're playing Emerald, Latios will appear if you tell your mom the color of the Pokémon was blue, or Latias will appear if you told her the color was red.
Capturing
Like the legendary dogs in Gold/Silver/Crystal, Latios/Latias can be found randomly in the wild and will flee the first chance it gets in battle. After you run into Latias/Latios the first time, you can track its location using the Pokédex's "area" function. Latias/Latios will move each time you move to a new area. One strategy for finding Latios/Latias is to move back and forth between two areas (for example: The Day Care and Route 117) and check the Pokédex to see if Latias/Latios has landed on the route you're on (in this example, you'd want to see Latios/Latias on Route 117).
Latios/Latias will be at level 45 once you find either or. Using a move like Mean Look, or inflicting sleep status will keep Latios/Latias from running. Have a lot of Ultra Balls handy; it may take awhile. If you inflict damage to Latias/Latios and then it flees, that damage will remain; they can't heal themselves. Don't KO Latias/Latios by mistake, for there's only one.
The Southern Island
The Southern Island is where you can find either Latios or Latias depending on your game. For example, in Ruby, Latios would appear in the wild and Latias would be at the Southern Island. To get to the Southern Island, you must have the Eon Ticket. How do you get this you ask? Well...um...there's no longer a way to get it. The Eon Ticket was given away in 2003-2004 at special Nintendo promotional events. You could mix records with someone who did get it through this way and then it would appear in your key items. Otherwise, you have to trade with someone who has Latios/Latias.
