ok
Go get a Relicanth from the Sootopolis-Mossdeep underwater and catch
it.Beware,its rare. Wailord is needed too.Train your Wailmer to level 40 and
evolve it. Have a pokemon knows dive and dive into the water at the current
between Pacidfilog and Slateport. (not the big 1 with tortoise rocks
surrounding.)Go all the way till you came to the Brialle.Dive up.Dig in front
of the giant Braille and put Relicanth in party slot 1 and Wailord at the
back.Talk to it and earthquake triggers.The doors then open.
Man I just dont know anymore.