Dendemille Town. And basically, she does just what it sounds like- for the price of a Heart Scale, she teaches your Pokémon level up or Egg moves they've forgotten, or moves from earlier levels they never had. --- http://www.fanfiction.net/s/9247960/1/404-Error http://gottaglitchemall.smackjeeves.com/
I've heard she can also teach high level level-up moves before the Pokémon normally has a chance to learn them. Is this true?
And how rare are Heart Scales in his generation?
It's true, some evolutions have moves they'd learn very late (like Aurorus learning Freeze-Dry at 77) that they can learn way before that with the move relearner. Or it can be moves they'd never learn on their own but are supposed to have known at some point (Talonflame and Flare Blitz). --- "Eat all your school, stay in milk, drink your teeth, don't do sleep and get eight hours of drug." Mr.T 3DS FC 2492-4153-0622
He teaches you moves you deleted or never learned from early levels.
Can he now teach your Pokemon anything in their move pool or something?
Hatched pokemon now "save" the moves they're hatched with, which the move relearner can teach again if they forget them, allowing egg moves to be relearned.
Some pokemon have moves that they "learn" twice, either at low level then high level, or as a "starting" move then at a higher level. Usually if they're caught they've already forgotten the move from the low level, but can learn it before hitting the high level from the move relearner.
Also the move relearner is a she in this game. --- The most exciting phrase to hear in science, the one that heralds new discoveries, is not "Eureka!" but "That's funny..."