save it for latios or latias, whitch is alot harder to catch than any other legendary. i caught all the regis and raquaza with ultraballs. see http://wiki.answers.com/Q/How_do_you_get_all_regies_in_pokemon_sapphire
in team aquas hide out
from your enemy teams base
I am pretty sure you get a masterball.
In team aqua's hideout
give a Pokemon the masterball and put it in the daycare with a ditto then it will be cloned!!!!!!
You must either get a masterball from team aqua base or game corner. Then you must fight a legendary and throw the masterball right away.
u run into her in random places u well want to keep the masterball
The professor
you can't
fire red: after you give the sapphire to celio, now you can trade with Pokemon ruby, sapphire and emerald
probably action replay but you can just buy a firered leafgreen sapphire or ruby and just save the masterball you get from them and give them to one of your Pokemon and migrate it
you can not get master ball in Pokemon emerald exsept in lotto in the big shop and in the agua cave. PS you can use a code