There are a few Pokemon that live underground such as Diglett and Dugtrio. Also, the move Dig allows Pokemon to burrow underground to attack their opponents.
No
There are no grass type Pokemon underground!
You buy it from any trap merchant underground.
go underground at heartthrone an Pokemon luage
Pretty much any where just look. if this does not help go on Google and put Pokemon diamond underground hikers (if u don't have diamond put which Pokemon game u have) That simple
You can't mine underground in either Pokemon Heartgold or Soulsilver, but you can mine underground in Pokemon Diamond, Pearl, Platinum.
pokemon black
In the Pokemon diamond underground.
no
None
You get underground by getting the Explorer Kit from the Underground man in Eterna city who's next door to the Pokemon Center.
You can find fossils in the Underground Tunnels, or underground. Just dig for them as you would spheres.