you can use an action replay.
it comes in a swarm
you cant get a diamond on Pokemon pearl but you can get a pearl on diammond ...and pearl.
you have to get the secret potion from Cynthia
train your Pokemon hard and feed it rare candys and if you want buy a ds action replay and you will get a cheat for infinity rare candys
27
cheat
ues rare candys
mt silver
you get a mewtwo then teach it rock smash use it give mewtwo three rare candys and choose the Pokemon you want to clone and vola you just wasted three rare candys
98746014
in your mount coronet
you can get it by this code 820258400044 in your pc