Kabutops can eliminate Golem/Rhydon with Surf before they can do anything. Snorlax can be taught Surf too, and he has high enough HP to survive any single attack in the game.
The best counter for rocks/grounds is Exeggutor. Great physical and special bulk, and he threatens things with Mega Drain (for Rhydon/Golem) and Psychic (Nidoking/Nidoqueen).
You probably have nothing to fear for single player though. --- Capt. Basch fon Ronsenburg, for Incitement of Sedition and the Assassination of H.R.M. King Raminas, has been found Guilty of High Treason and put to his Death.