Always remember this: Pokéballs work good on legendaries. Don't use high-class balls and stuff, because legendaries can be caught easily in Pokéballs. So I would stock up. Hope I helped! :)
You can get Latias? Oh right! Use a masterball for a guarantee catch, if you are a button masher use any pokeball.
You can't. Latias is only available in heart gold. You might be able to trade it though.
I say just do what u want and level him up because my LATIAS is level 68.
-Golden Feather -Bell -Kimono Girls -Master Pokeball (WILL NOT FAIL AT ANY CATCH ALAWAYS WILL CATCH POKEMON)
Latias is only available in Heart Gold.
Other than the masterball try using a lot of ultra balls.
A Master ball is the best pokeball in the history of Pokemon. You may not have 900 masterballs like i do, but if you purchase an action replay which they sell at target for $20, it comes with a cheat to get all pokeballs x 900. that is the best way to catch every Pokemon there is.
A Dark Ball could work nicely here, since you're in a cave.
You have to chase it around cause it is really hard to catch latias in heart gold cause it runs away and by the way if you are trying to fly where latias is latias does not show up so look in the map.i hope this is helpfull
Try the Timer Ball.
in soul silver you get latios but you'll have to trade with some one who has heart gold to get a latias.
you can catch lugia ho-oh suicune raikou and entei latios on soul silver and latias on heart gold groudon on soul slver and kyogre on heart gold arcticuno zapdos and moltres hope this helps:x