In the game, there are People that will teach move to one of your Pokemon. They only teach the move ONCE!



Rollout:

I think you might already know where he is. He is one of those fat guys and he is in Maville.



Fury Cutter(Pretty Close To The Rollout Guy):

He is in Verdanturf. Go in the Pokecenter and some one in there will teach a Pokemon Fury Cutter.



Swagger:

You know the Pokemon Fan Club in Slateport? Well, in the fan club there is a boy that is willing to teach Swagger.



Dynamic Punch:

On the Mossdeep beach, there is a karate guy and he will teach the move Dynamic Punch. I taught this move to my Groudon.



Sleep Talk:

In one of the treehouses in Fortree, there is a grandpa that will teach a Pokemon the move(This move SUCKS!).



Double Edge:

In Sootopolis, in the Pokecenter, there will be a girl looking at the book shelf. She will teach the move.



Explosion:

In Pocificlog, there is a boy looking at the table in the Pokecenter that is willing to teach Explosion(!).



Metronome:

In the Verdanturf Pokemart, A girl in there will teach the move.



Substitude:

On the top of the Department Store, in Lilycove, there is a girl that will teach the Move.



Mimic:

In Lavaridge, in a house, there is a ninja kid or some one that will teach it.



P.S. I think this works on Ruby and Sapphire; I have not tried it yet!

Skyp