Pollution Pool (ガラクタの みずべ?) is the third main area in the Ravaged Rustworks. This area has a few ponds where Captain Olimar can to swim through, but his Red Pikmin and Yellow Pikmin cannot, so they need to stay behind resting on Seeding Dandelions in platforms, until Olimar calls them to the other side, or he builds a bridge with Blue Pikmin to allow passage. This area also contains the game's only Elongated Crushblat. If the player goes back to one of the first ponds and uses Blue Pikmin to clear the way, they can access a pathway that leads to the secret exit, which in turn unlocks the Drenchnozzle Den. The normal path unlocks the Space of Silence.
This area alternates a lot between land and underwater locations. The level also relies on Seeding Dandelions, which are important in order to progress in the area, since they can allow non-aquatic Pikmin to wait for Olimar to return, when he's in the underwater portions of the area. Some time after the beginning of the level, the player has to throw their Pikmin on a big wooden stake in order to get some Yellow Pikmin, that are necessary to destroy the electric gate located nearby. After some walking in the area, the player can climb up a vine, and get access to a doorway. On the other side, Olimar can retrieve the Life-Form Prototype. After some time, the player will be forced to leave their Pikmin on Seeding Dandelions, in order to go in the water and get some Blue Pikmin, that are necessary to build a bridge, and get the Almighty Ruiner, as well as the Bond Impressor. After that, the player can go to the normal exit, but there is also a secret exit in this area. For that, Olimar has to turn back in the area and go to the door next to one of the first ponds of the level. With their Blue Pikmin only, the player has to dive into the water, and go through some doorways, allowing the protagonist to get his non-aquatic Pikmin back. Then, the player can reach the secret exit.
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