Unova's Survival Crisis - S15.E49

With Meloetta in their possession, Team Rocket's Giovanni controls Tornadus, Thundurus and Landorus in their more powerful Therian Formes though use of the reveal glass unlocked by Meloetta's presence and Meloetta's song. Ash, Cilan, Iris, Cynthia, and Ridley do their best to free Meloetta and save the world from Team Rocket. But forces stronger than Team Rocket are present, and Giovanni soon finds himself not able to control himself and sets Tornadus, Thundurus, and Landorus on a path to destroy Unova rather than take it over for Team Rocket.