Null

null is an area in Pikmin: The Last Battle that becomes accessible after defeating the Plasm Wraith in the Final Challenge, which closes off with the explanation that returning there is unnecessary, and having collected the remaining treasures during the final five days on PNF-404. It is a dark arena in which the true final boss, Pollutant, is fought.

Plot
After defeating the wounded Plasm Wraith, Olimar, Shacho, and the Koppaites escape, only returning after collecting the last treasures on PNF-404. Upon return to the area, they find it completely dark, with a strange creature near the landing site. After defeating the creature, they can leave the planet in peace.