As the home of the Bulborbs, this place is sprawling with them. It is recommended that you muster an army of Pikmin before setting foot inside of this dimension. Of course, once you do, the Bulborb's Lair can provide players with rewards for conquering its Emporers, and Bulborbs will provide you with plenty of corpses for your Onions... provided you don't lose more Pikmin than you can make.
The Portal
The Bulborb's Lair dimension can be accessed by creating a portal frame out of granite. It is speculated that this is how Bulborbs travel back to their homeland as well. However, the portals to the Bulborb's Lair wouldn't just let anyone through, only their own kind. You will have to trick the portals to let you through by activating the portal with a Bulborb's Eye.
Resting Grounds
Mobs that Spawn in this Biome:
Emperor's Sandpit
The Emperor Bulborbs dwells in this biome, usually in slumber beneath the sand. They will grow quite the temper when disturbed.