First of all get lots of different kinds of pokeballs and catch a wailord and a relicanth. Once you've done that go to Pacifidilog town and go all the way south. Then surf west through the currents keeping south at all the times. I can't tell you the rest but when you reach a diving point dive down into it. Go south until you get to some dots on the wall. Go up to them and press B. When you get to the surface get onto the land and go all the way north to you get to that riggid wall. Use dig and it should open. Then put Relicanth at the front of your party and Wailord at the back. Leave it and it should say "You heard a door open far away" or something like that. Then get out of that place and fly to Dewford. Walk up north then surf west until you can go north. When you see a island with trees on it on your westgo on it. Cross the island and surf up north. There will be a little cave. Go into it and go up the wall and press A. Leave the dots on the screen for 1-2 minutes and it will open. Press A on the silver rock and prepare to catch a level 40 regiice.