If you want to know how to make the Secret Base in Pokemon BDSP Grand Underground or Brilliant Diamond and Shining Pearl, the first thing you need to know is that you’ll have to work for it. You have to progress far enough through the game to earn your way down into the Underground in the first place. Then, you have to put even more effort into getting the proper tool. If all this seems a bit daunting, don’t worry, we’ve got you covered with this guide.
How to Make Secret Base in Grand Underground – Pokemon Brilliant Diamond and Shining Pearl
To make your Secret Base in the Grand Underground in Pokemon BDSP, or Brilliant Diamond and Shining Pearl, you need to obtain the Digger Drill. In order to get that item, the first step is to get to Eterna City, where the second gym is. Go into the house next to the Pokemon Center and talk to Underground Man. He gives you the Explorer Kit, which lets you dig your way to enter the Underground. After you spend some time in there, go back up and talk to the same guy again. He will instruct you to go down and dig for treasures, so do just that.
All you need to do is find one gem in the walls of the caverns. Find the little yellow sparkle on the map, and when you’re close, hit the R button to use the radar and locate where the jewel actually is. Dig it out of the wall and report back to Underground Man to make the Secret Base in Grand Underground in Brilliant Diamond and Shining Pearl, aka BDSP. He should then give you the Digger Drill. The conversation will end with him saying “what shall I assign you next?” When that happens, talk to the man again, and he will explain how to make your Secret Base.
Go back into the underground and just pick any wall you want. Use the Digger Drill, and that will automatically create your secret base. You can visit it whenever you want and place stuff like statues in there. Just remember where you put the base, or take a screenshot of the map or something, just in case.