Waterwraith

The Waterwraith is a minor antagonist and the boss of the cave Submerged Castle, a cave that was explored by Captain Olimar in Pikmin 2, and by Aqua and the Blue Scouts in The Lost Pikmin Season 4 Episode 8 in order to get the interdimensional crystal.

Captain Mark warned the Scouts about the main danger of the cave: If staying on a sublevel for five minutes, the Waterwraith will spawn and chase after the Pikmin to crush them with its rollers, and he was absolutely right, it falled from the ceiling in Sublevel 3 and murdered one of the Scouts. So far, the two remaining Pikmin including Aqua successfully escaped the monster to Sublevel 4, and the Waterwraith growls in frustration.

Trivia

 * According to Dr. Pikmin, this creature comes from the dimension of the rift like the Mysterious Life Form.