Is there such a thing as an Experience Multiplier Mod for Pokemon Black/White?

[PitchPine]

I'm currently editing a Pokemon Black .nds file and I wish to make the game harder by multiplying the gained experience by 0.75 or maybe 0.5.

I'm aware this could be achieved by using AR cheat codes, yet I would prefer to edit the .nds file directly instead.

Is there any modding tool or method that would allow this?

 

Thanks in advance.