What level does rhyhorn evolve on?
Rhyhorn indeed evolves to Rhydon at level 42. Then, you can evolve Rhydon into Rhyperior (number 464 in the National PokÃƒÂ©dex) if you trade it while holding a protector. You might want to delay the evolution of Rhyhorn, so that it gets certain attacks earlier. For example Megahorn on level 67 (Rhyhorn) instead of level 77 (Rhydon and Rhyperior).