How to Get Rhyperior in "Pokemon SoulSilver"by Melissa King ; Updated September 22, 2017
Ground and Rock-type Pokemon are amongst the toughest team members available in "Pokemon SoulSilver." The vicious Rhyperior combines solid defensive armor and powerful stone claws to create an unstoppable force, even when fighting against the strongest creatures. But obtaining Rhyperior and his overwhelming power is not a straightforward task. Before you are able to become the owner of a Rhyperior, you need to find and evolve its lesser form, Rhydon.
Head to the Safari Zone once you have beaten the game. The Safari Zone is located to the left of Cianwood City. Inside the Safari Zone, the attendant gives you 30 Safari Balls to use for catching Pokemon.
Go to the Savannah area of the Safari Zone. Walk around until a Pokemon attacks you. There is a chance that the Pokemon is a Rhydon. If it is, throw one of your Safari Balls at it to capture the Rhydon.
Go to Mahogany Town and walk left along Route 42. Enter Mt. Mortar when you reach the cave door.
Walk through Mt. Mortar until you see a rocky cliff and a ledge above you. Use the Rock Climb move to ascend to the upper level. At the top, you will find the Protector item in a chest. Once you have it, leave Mt. Mortar.
Pause the game and select Rhydon from your list of Pokemon. Choose the "Give Item" option and select "Protector."
Sit in the same room with a friend who is also playing "Pokemon SoulSilver." Enter any Pokemon Center and walk to the Union Room on the second floor.
Talk to the woman at the counter and select "Trade." Choose the Rhydon holding the Protector as the Pokemon you want to trade. Have your friend accept the trade when a message appears on his Nintendo DS. The Rhydon will evolve into Rhyperior upon completion of the trade.
Instruct your friend to trade the Rhyperior back to you after the evolution is complete.
If you do not have a friend to trade with, it is not possible to evolve Rhydon into Rhyperior: There is no alternate evolution method.