Things You'll Need
Instructions
Travel to Kanto after defeating every Gym Leader in Johto, the starting region. Win against the Pokemon League in Kanto. Fight Brock, Misty, Lt. Surge, Janine, Sabrina, Blaine and Blue to collect the second set of eight badges.
Enter the following code into Action Replay: 9224670a 00002101 1224670a 00002100
d2000000 00000000. Add the code to the "Pokemon SoulSilver" cheat codes list. Name the cheat "Catch Trainer Pokemon."
Start "Pokemon SoulSilver" after enabling the newly added cheat. You will be able to catch Pokemon that belong to other Trainers with this cheat activated. Ask Daisy Oak to massage a Pokemon five times.
Raise the massaged Pokemon to full happiness and show it to Daisy Oak in Pallet Town. She will give you Blue's phone number, which will allow you to rematch Blue. Purchase a few Ultra Balls, unless you plan on using a Master Ball to catch the Rhyperior.
Call Blue on a Sunday night to rematch him. Defeat every Pokemon until he chooses Rhyperior. Weaken the Rhyperior and throw Ultra Balls or a Master Ball to capture the Pokemon. The Pokemon will be hard to capture, since it is Level 70.