first you need to get the national dex to do this you need to see all Pokemon in sinnoh to compleat the national dex
see all Pokemon on the poke dex
cach pearl the legndary Pokemon
i smell bad
past floroma.
you have to have action replay
You have to beat the league.
YOU WILL NEED TO GET A STARTER POKEMON ok.
Turn left at the bridge, straight on past the Pokemon Centre, right past the Pokemon Mart, through the temple of flag, then there you are!
You need action replay to do this cheat but it is only on Pokemon pearl
Beat the GYM LEADER [=
Complete sinnoh dex
You don't.
Go through the cave