Join Nix across the hell that is Kanto and all its Pokemon, specifically the poison types. oh god, the poison types...
Mostly Basic rules:
1)Pokemon faints, it dies.
2)Can only catch the first pokemon on a route
-If it's a duplicate you may retry
-Exceptions include shinies and gift pokemon
-No catching Legendaries
-Each area in the safari zone counts individually
Mind spoiling the answer to the "what do Pi and Diglett have in common" question?
My only guess is that there are round and by cheating somewhat that their Johto dex number is 134. By a long shot there also the nose being the cherry on top? I'm doubtful that is right though but then again you did add a cherry to the image.
@onyxr: Actually, do you realize that Diglett have been confirmed to have some sort of feet? In Pokemon Mystery dungeon: Red/Blue Rescue Team, a Skarmory kidnaps one and after you have rescued it, it says, "my FEET still feel like they're walking on air."