you need aurora , mystic ticket to go to islands to get rare pokemon (ignore rere i ment rare)
You don't.
you cant get regigigas on Pokemon emerald its to ew of a Pokemon
from boos and from mali
in a cave at the town after sootoplis
trade from leafgreen or firered
this is impossible!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
There was never any Pokemon events for emereald.
in route 111,114,120 it is common their
Cutter's House in Rustboro
Get it in the contest hall in slateport city.
It is given to you by a fisherman on Dewford.
Trade with someone that did the events. That's about the only way.