The Mysterious Life-Form (Mysterious Life Form in Europe, 謎の生命体?, lit.: "Life Form of Mystery") is an enemy in Pikmin 3 and the alternate form of the Plasm Wraith. In this form, it looks like an amorphous blob of translucent plasm. It follows Brittany, or whoever is guiding the Pikmin carrying Captain Olimar, through the labyrinth that is the Formidable Oak. Once Olimar is outside, the creature turns into its original form, the Plasm Wraith.
Pikmin 3 Prima Guide
“Before the Plasm Wraith reveals its true self, it appears as the Mysterious Life-Form. This giant, slow-moving creature uses its amorphous body to absorb its victims. It's best to simply avoid the Mysterious Life-Form. However, if a battle is unavoidable, wait for the creature to turn an opaque gold color before you attack. When the creature is translucent, attacking Pikmin will simply be absorbed by the Mysterious Life-Form.”
When first spotted atop the mound that forms the Formidable Oak, the Plasm Wraith transforms into a spherical blob and envelopes Olimar in order to protect him, but the Koppaites order the Pikmin to destroy it. They decide to carry Olimar back to the S.S. Drake, but as the Pikmin cannot see a way back, it's decided to have them follow Brittany, and the Koppaites enter the cave system. As soon as they enter, the Mysterious Life-Form drops from the cave ceiling and begins chasing the player through the cave. The player must stay ahead of it while overcoming the various obstacles present within the cave system in order to safely escape.
The point of the confrontation with the Mysterious Life-Form is not to destroy it, but to escape from it. There are a few notes that you should consider:
After you successfully escape the cave system, you will arrive in an arena outside near the S.S. Drake. When Olimar reaches the exit as well, the Mysterious Life-Form will come out too, revert to its original form as the Plasm Wraith, and detain Olimar inside its body, thus commencing the final boss battle.
Because the explorers do not know about this form of the Plasm Wraith, they simply nickname it "Mysterious Life-Form". In Europe, it's spelled as "Mysterious Life Form". In Japan, it uses the same name, 謎の生命体?, which translates to "Life Form of Mystery". Internally, it is called
Names in other languages