Digger Drills are how you create Secret Bases in Pokémon Brilliant Diamond and Shining Pearl. You’ll need these if you want a location to place your Statues down to increase the odds of specific Pokémon appearing in the Grand Underground while you’re exploring it. The Digger Drills are consumable items. You’ll more if you want to build additional bases during more Grand Underground explorations. Here’s where you need to go to get more Digger Drills in Pokémon Brilliant Diamond and Shiny Pearl.
You’ll need to find one of the Hikers walking around the Grand Underground. You can find them while running between the various biomes that appear in this region. Speak to the Hiker, and ask them for the ‘Get goods’ option.
You’ll pull up the Hiker’s available inventory. They should have Digger Drills available for eight blue spheres. You can obtain these blue spheres by mining at the fossil points in the Grand Underground, which are the orange icons on your map. Approach these locations to start the mining minigame, and hopefully, you walk away with some spheres. You can find several unique spheres, such as Red, Blue, and Green.
The mining minigames are tough, but the more you explore the Grand Underground, the more opportunities you’ll have to obtain them to create Secret Bases.