From Pikmin Fanon
This article or section presents information pertaining to Pikmin: The After Years, created by Gamefreak75.
The Sandy Abyss is most likely the last cave entered in Dreary Dunes in Pikmin: The After Years. It is a very challenging cave with a tough boss. Many sandy enemies appear here, and many bomb rocks drop from the ceiling of each sublevel.
When defeated, the Raging Long Legs will drop a treasure called the Crystallized Rage.