How do you catch Latios after you've seen it only once when it keeps changing its location before you even get to find it?

Answer 1

you catch a Pokemon with mean look or spider web and use it and then it wont flee.

One...Save Your masterball if not then

two... buy about 40 max repels and get a dusclops with quick claw and surf using max repel with strongest Pokemon in front (Lv 40 or above)

Answer 2

You don't have to migrate in ruby, sapphire or emerald you can find it after beating the game on any route if you want it in diamond, pearl or platinum then you have to migrate it from those games mentioned above.

Answer 3

You cannot catch Latios in Pokémon X, in order to receive one in X, you will need to trade for one or you will need to use the Poké Transporter in order to transport one from one of your previous games.

Answer 4

You got to be lucky,but you can catch it.In my Emerald,it appears mostly in Lilycove city...