Got this idea while looking at one of the tvs in pokemon white so like the game I'll describe certain items.Now here are two free items only in pokemon black 2 and white 2.This won't be how I'll normally do it but here they are.
Oval charm and shiny charm
Oval charm make it easier for the day care man to find eggs in the day care. Gained by finishing the unova pokedex. 
The shiny charm is exactly how it sounds this makes it easier to get shiny pokemon not by much but still.The odds are normally at 1 in 1,365.3 to 1 in 1024. This is gained by finishing the national pokedex.
