In *Pokémon the Movie: Diancie and the Cocoon of Destruction*, Nyarth (Meowth) operates with Team Rocket members Jessie and James. Targeting the Mythical Pokémon Diancie for its ability to create diamonds, they successfully abduct it. Taking Diancie to a clock tower, they demand diamond production. Diancie complies, generating diamonds that accumulate until the clock mechanism stops. Distracted by the diamonds, Team Rocket allows Diancie to escape with Millis Steel's help; the diamonds later vanish, being temporary creations formed before Diancie received Xerneas's power.

Team Rocket pursues Diancie into the Allearth Forest. There, various groups including thieves and the Steels clash over Diancie, disturbing the Cocoon of Destruction and awakening the Legendary Pokémon Yveltal. During Yveltal's rampage, Team Rocket and their Pokémon are petrified by its destructive power. They are later revived when Xerneas uses its life-restoring abilities on the forest and its inhabitants. Team Rocket's actions directly contribute to Yveltal's awakening but result in no lasting changes to their role or objectives.