For Diamond, you have to beat Cyrus then he'll give you a Master ball. After that, go to Mt. Coronet and beat all the Galactic Grunts there. When you are at the top, go through the entrance to Spear Pillar. After that, you have a tag battle with Barry against Mars and Jupiter. Beat them … Read more

You need strength and I think rock smash as well. Defog is not required but it helps. Go to celestic town and go to mt coronet. Go upwards (use your map to help) until you arrive at a snowy route. Keep on going upwards and turn left or right if there is a dead end. … Read more