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Poipole's world (Japanese: ベベノムの世界 Bevenom's world) is an anime-exclusive location found in Ultra Space. It debuted in The Shape of Love to Come!. It is the home to a horde of wild Poipole, including the Poipole that belonged to Ash; the horde is led by a Naganadel.
Poipole's world was once filled by the light of Ultra Necrozma, which made the world a lush and green planet. Although it would often protect the Poipole and Naganadel, one day a meteorite came crashing down and in order to protect the world from its impact, Necrozma collided with it. But in destroying the meteorite, it turned into a different form with a black appearance and fell into a crevasse. After falling, the change in Necrozma's form caused it to be encased in a spiky and crystallized cocoon and turned the green and bright world into a desolate and dark place. The Poipole and Naganadel huddled together and attempted to take in the remnants of light left. A sole wild Poipole later left the world, attempting to find a better place to live. Soon after, a Solgaleo and Lunala came to the world through an Ultra Wormhole, causing Necrozma to awaken and begin attacking them in an attempt to absorb their light.
Poipole's world first appeared in The Shape of Love to Come!, during Poipole's dream, where it was seen talking with the ailing Naganadel. The Ultra Guardians then came to the world through an Ultra Wormhole produced by Lunala in The Prism Between Light and Darkness!, in pursuit of Necrozma, who had taken over the body of Nebby. The Guardians are attacked by wild Poipole, but soon relent when Ash's Poipole talks to them. Naganadel then appears from the hive interior to check on the commotion, but soon collapses from weakness. Everyone goes into the hive's interior, where after being fed a batch of Sitrus Berries, Naganadel feels well enough to talk. Through telepathy, Naganadel relays the history of its world to the Ultra Guardians. It then pleads the Ultra Guardians to allow Necrozma to absorb Solgaleo and Lunala's light so that their world can be saved.
Their discussion is interrupted by Necrozma and Lunala, who had begun their fight anew in front of the Poipole hive. Gladion attempts to intervene and help Lunala, but is eventually stopped when Ash and his classmates come up with a plan to help both Necrozma and Nebby. Ash and Pikachu, Kiawe and Marowak, Lana and Popplio, and Gladion and Silvally launch their Z-Moves at Necrozma to share their Ultra Aura with it, but, as shown in the following episode, the plan backfires, and only succeeds in making Dusk Mane Necrozma stronger. It is then that the Ultra Guardians home base establishes communications with the team. After Lusamine, Professor Burnet, and Wicke explain their findings, Lusamine coordinates with the Island Kahunas to channel the Ultra Aura of every person and Pokémon in Alola. Combined with the Ultra Aura from Nebby and Lunala's respective Z-Moves, Necrozma, and Poipole's world, are finally restored to their former glory.
After the battle, Ash and Pikachu share a tearful goodbye with Poipole, who chooses to remain home with its kind.
Poipole's home world without Necrozma's light
The interior of Poipole's nest
Pokémon seen in Poipole's world