use your explorer kit
You have to go to the underground.
Go underground
No. The underground is only in Pearl, Diamond and Platinum.
go underground and mine
you need to go underground
you have to go underground and dig for him
In the Pokemon diamond underground.
You cannot go underground as you were able to in Pokemon Diamond and Pearl. You are stuck above ground in Pokemon SoulSilver. You get two regions to go between, though.
Go underground and start diging
You have to be lucky and go underground and dig!
go underground with explorer kit and get a claw fossil
You can find it somewhere or you can go underground and dig it up.