>>58316755on booting game, interact with painting in lilycove to seed the rng because emerald is bugged and always has the same seed every time you play
fly to route
have fainted lead with illuminate to increase wild encounter rate
use white flute to increase wild encounter rate further
have second lead the same level as the pokemon trying to catch with the ability synchronize and the same nature you want your shiny to have (50% chance your shiny will have this nature)
give that pokemon smoke ball to increase run away chance to 100%
use repel to make pokemon lower than the level as your second lead not show up (increase chances of getting the shiny, in this case ralts goes from 4% to 10%)
use the acro bike and hop in place so that you can look for pokemon without repel running out
that's all the things i'm doing, on two copies of emerald. one is in my gba, one is in my ds