There are only 2 ways to catch Latias in the game.
The first is catching her as a roaming Pokémon, and in order to do that, you must first beat the Elite Four. After the credits have rolled and you resume the game in your house in Littleroot Town, your mother will be seen watching a broadcast about a Pokémon roaming the Hoenn region. After the broadcast is over, she will ask you what color Pokémon they said was roaming. To catch Latias, you must answer red. After that, you will be able to find Latias anywhere in grass or on the water. The easiest way to encounter her is by moving a Pokémon to the front of your party with a Level no higher than 40, and then using Repels while moving through tall grass in an area where wild Pokémon are never higher than 40; with luck, Latias will appear. This method takes luck, and quite a bit of trial and error, but it typically works better than the alternative of encountering the Eon Pokémon by pure luck.
Like all roaming Pokémon, Latias will flee from battle at the first chance she gets, so it's a good idea to save your Master Ball for this encounter. Alternatively, after you encounter her the first time, you can track her with the PokéNav, to determine where she is. She still moves around a lot, though, so you'll still need luck to catch her.
The other way to catch Latias is by using the Eon Ticket, a special Item that can be obtained by scanning an Eon Ticket card through an E-Reader device, though both are hard to come by nowadays, or else by going to an event. Anyway, to use this method, you first have to make sure to choose blue for the question mentioned previously, then talk to the man in charge of the ferry in Lilycove. He will react to the Eon Ticket, and from then on you can access the hidden location, Southern Island. Go there, and you will find very little of significance, but within the island's depths, there is a single stone pedestal. Examine it, and Latias will approach you and attack. There are two things to be wary of with her in this encounter: she is at Level 50, and she holds the Soul Dew item, which makes her attacks 50% more powerful.
In case it's not clear, choosing blue makes Latios appear in place of Latias, also at Level 40, and if Latias is selected as the roaming Pokémon, Latios will appear at the Southern Island, also at Level 50 and holding the Soul Dew.
No, you can only get Latias in Sapphire and Emerald and Latios in Ruby and Emerald.
The only way to get a latios or latias in your Diamond or Pearl is to migrate, latios from Ruby or Emerald. latias from Sapphire or Emerald.
you get latias and latios everywhere you just have to look very hard latias is mostly by slateport city and mauville city route 110,103. latios is mosty by forttree city and and lilycove city route 120,121,123.before getting latios and latias get a lot of ultra balls (save your master ball(s)!but you have to beat the elite four first to catch latios and latias.
latias/latios/deoxys/jirachi/groudon and kyoger
need to migrate or trade
No, you can only get Latias in Sapphire and Emerald and Latios in Ruby and Emerald.
One way is to trade with another emerald or you could trade your latias (or latios) to another emerald then restart the game and choose the opsite then catch it and trade back.
randoom agen!
That's not possible latias and latios are caught in ruby, sapphire or emerald you must trade them to firered to get them.
you go fly in the air and catch him with a net
For Pokemon ruby you can catch the three regis, rayquaza, groudon, and latios/latias. In sapphire you can catch the three regis, rayquaza, kyogre, and latios/latias. However, in emerald you can catch kyogre, groudon, rayquaza, the three regis, and latios/latias.
It is possible, but you can't catch them both on 1 Pokemon game. If you have Pokemon Emerald, Ruby and or Sapphire. Then you can get them both. For example: Someone trade Latios and you have Latias, trade an another Pokemon for Latios and you have them both.
all i know is how to get the regis and latios or latias.
latios and latias appear in random patches of grass and areas of water after you catch Rayquaza or make him faint.(after saving the world in Sootopolis.)
If you want to catch Latios or Latias in Emerald, follow these steps. #1Beat the Elite Four. When the credits end, go to the TV. The TV will say something about a Pokemon soaring through the sky. Then it will ask what color it was. I recommend blue. #2Wonder the Hoenn Reigon. Eventually, you'll find Latios or Latias -SLICK
The regis(except regigegas),raquanza,groundon,kyogre,and latios or latias
You can fight in the battle tower, catch the three regis, search for latios/latias, or in emerald you can catch groudon and kyogre