Use this:http://pokemondb.net/pokedex/cloyster/egg it will kinda show you how to get rapid spin on anorith, or you could trade with somebody that has one, or hack. Hope I helped(ish)!
You need to breed Rapid Spin from the Blastoise-line to the Kabutops-line and then on to a Anorith. You can also breed a Anorith with any member from the Tentacruel-line or Cloyster-line, however, these Pokémon don't learn Rapid Spin by levelling up. Source: http://pokemondb.net/pokedex/kabutops/egg#move-rapid-spin http://pokemondb.net/pokedex/anorith/egg#move-rapid-spin
