Actualy you can. First you need a Relicanth (a rare underwater Pokemon) then a wailord (or just raise a wailmer to level forty) and any Pokemon how knows DIG. After that go to pasifilog city, find a path of that puts you in a place you can use DIVE, use DIVE find a door and go through it then surfise.You will be in a place called sealed chamber walk to the back (with wailord first in your party relicanth last) and use DIG. Then find Registeel's tomb (near lilycove) OR Regirock's is in the desert (very bottom) and Regiice's is around dewford. hope I helped ; ]
Go into the middle of the room and use FLY (like if you were going to fly to a different town) That should open up the braille door to the north, and you can fight Registeel!
Not that I know of I have a cheating device and there isn't a cheat for that so besides walking through a door no you cant walk through walls.
use flash in the middle of the tomb
the door will be open after you solve the crisis between kyogre and groudon.
you find raquyza at the sky pilliar
You cant
At the end of iron island there is a dark door(you have to have beaten the elite 4)
Just In the second door upstairs the Pokemon center.Answerwhen you give the ruby and sapphire to Celio AnswerYou need to give the blue and red stones to Celio on island one in Pokemon FireRed and in Emerald you need to have beaten the champion and elite four.
Go inside Registeels tomb(after going to sealed chamber.) Read the wall. It says "To those who inherit (something), shine in the middle. Translation: Use flash in the middle of the cave.
go left then right then you wiil see a door go inside it and there you have it
walk in the front door... you cant go into the little pin where the Pokemon are.
i think you need a e-reader to skan Pokemon cards(trainer card=trainer in back room Pokemon card=Pokemon in back room, this might work in sapphire & rube aswell).