Along the same lines as my "Bulbasaur, but with a lightbulb instead of a plant bulb so it's Electric-type now" drawings from last week...
...Here's the Gastly family if they were part Ground rather than Poison! They start out relying more on their ability to phase through solid matter, then gradually accumulate greater and greater strength for actually physically digging through the ground... and also lifting bigger and bigger stones, of course!
The fully-evolved form is basically a "Gengar-ized" version of a Pokémon I made up waaaaay back in the day (probably around 1999-2000?), a Ghost/Rock type called Phantomb. If you ever came across the "Pokémon Factory" website, you might have seen Phantomb in their second-generation gallery -- it was one of the three or four ideas I submitted to the site back then which they accepted and added to their Pokédex. Phantomb's PF sprite ended up pretty much exactly as I had described it -- based very closely on a "ghost carrying a gravestone" enemy from Startropics 2: Zoda's Revenge, which was one of those NES games I played the hell out of when I was a kid.
