Cube Fortress

Adudu's Underground Headquarters is located very, very deep under the Rintis Island Junk Shop, the underground cave headquarters is a replacement for the Spaceship since Probe sold it to Bago Go (Episode 24).

History
After Probe had sell Adudu's Spaceship to Bago Go (Episode 24) and lose against BoBoiBoy in the Season Finale, Adudu decided to dig very deep in the Junkshop so he could make his Headquarters and also their new home (Episode 27/Season 2 Episode 1 Pt.1).

Here's a pic of the Headquarters