Pokémon : S21 | E30 – Why Not Give Me a Z-Ring Sometime?

When James's Mareanie learns a Dark-type move, Team Rocket realizes this could be their chance to use their Dark-type Z-Crystal. The Boss sends them to Ula'ula Island to get a Z-Ring from the kahuna, who's a former associate. Meanwhile, at the library, Acerola tells the story of the Greedy Rapooh—who turns out to be a real Gengar with thieving tendencies, and who steals Team Rocket's Z-Crystal and takes off with Acerola on its back! When Kahuna Nanu sees that Team Rocket is battling to rescue Acerola, who's his niece, he lends them a Z-Ring—and after the battle, Acerola gives them a special Z-Crystal for Mimikyu! (Source: Wikipedia)