The Great Underground in Pokémon Brilliant Diamond and Shining Pearl is a vast space below the surfacr of Sinnoh that players can explore. In it, Trainers can dig for treasures, encounter plenty of Pokémon, and even set up a Secret Base.
While running around the many tunnels, you're likely to see Diglett and Dugtrio. However, these aren't Pokémon you can battle, so what exactly are they for?
What does Diglett do in the Grand Underground?
When in the Grand Underground, you'll see a gauge in the top right corner, just below the minimap.
When you see a Diglett or Dugtrio, it'll disappear as you run towards it, leaving behind a kind of pink sparkle.
Running over this will fill the gauge -- one point for a Diglett, three points for a Dugtrio.
Once the gauge is full, you will see a message -- Something good may happen in the Grand Underground!
For the next four minutes, you'll benefit from two bonuses.
The first is an increased chance of finding a Gorgeous Stone Box, which contains a shiny variant of a Pokémon Statue. These have a luxurious jade-like appearance.
The second benefit is double the chance of shiny Pokémon appearing in the many Hideaways. Typically this is a 1-in-4096 chance, so now it'll be 1-in-2048.
While slower that using the Poké Radar, increasing the Diglett counter is a good way for players to shiny hunt.
An effective way of increasing the gauge quickly is to place your Secret Base next to a Diglett spawn.
Check that the spawn is consistent before using your Digger Drill, then just keep entering and exiting the base, picking up the Digletts until the gauge is full.
A huge part of the Pokémon experience is hunting for shinies, and the Poké Radar is a key tool. Here's where to get it and how to use it in Brilliant Diamond and Shining Pearl.
