Pikmin 3: The Dweevil's Revenge/Pit of 100 Trials

The Pit of 100 Trials is an optional cave but you need to do it in order get 110%. Oddly it only has three treasures, one on floor 50, one on 99 and one on 100

Floor 1
This floor is fairly easy, only an Orange Bulborb and some Skitter Leaves block your progress.

Floor 2
also a bit easy just 2 dwarf blue bulborbs and a Blue Bulborb. but be warned as there is tons of water.