Rhyhorn indeed evolves to Rhydon at level 42. Then, you can evolve Rhydon into Rhyperior (number 464 in the National Pokédex) 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).
Rhyhorn will evolve to Rhydon at level 42.
Rhydon doesn't evolve by level. When the Protector is attached to Rhydon, trade it and it will evolve to Rhyperior.
Basically Rhydon doesn't evolve on a certain level. You need to have Rhydon hold a Protector and Trade it, with a another person.
Rhyhorn evolves into Rhydon at Level 42. Rhydon can then evolve by attaching a Protector to it and then trading it.
Rhydon evolves by trade, not level. Attach the Protector to it, trade it, and viola! Rhypherior at your command!
trade it with a protector Actually that is not correct. You need to give protector to rhydon and then trade him to get a Rhyperior. If you want your Rhyhorn to evolve, just train him and when he reaches level 42, it becomes Rhydon.
Rhydon is not able to evolve in FireRed.
..........level rhyhorn to 42.....get a rhyhorn from safari and evolve it to rhydon
Rhydon, in Pokemon FR/LG, does not evolve.
Rhyorn evolves into Rhydon at level 42 which evolves into Rhyperior when traded while holding a protector.
Rhydon at level 42. Rhydon evolves into Rhyperior when it is trading holding a Protector.
rhyhorn Evolves at level 42, NOT Rhydon you.... Okay I'm going to say it but I still feel it inside.
Rhydon evolves when you trade it while holding a protector.