Expedition to Onix Island! (Japanese: イワークの島でサバイバル！Survival on the Island of Iwark!) is the 87th episode of the Best Wishes series, and the 744th episode of the Pokémon anime. It first aired in Japan on July 5, 2012 and in the United States on November 10, 2012.
At Cynthia's house, Ash, Iris, and Cilan are training for the Junior Cup. Dawn decides she needs a break from the training, and suggests they visit a nearby island, known of a special giant Onix. They arrive on the beach where Cilan prepares food for them. All ready, enter the huge cave inhabited by the wild Onix.. The enraged Onix attack them, and they flee. Iris and Dawn hide in a wooden area, and Ash, Cilan and Piplup hide in a forest clearing, therefore the two are separated. Meloetta attempts to calm the Onix down with its songs, but fails. Meloetta then transforms into Pirouette Forme. It uses an awesome close combat, after which they flee.
Still in search of the special Onix they are cornered by group of Onix about to attack them. Meloetta again sings a song but the Onx are persistent. Suddenly, a huge roar of an Onix is heard. A coiled-up shiny Onix reveals itself, causing all other Onix to flee. The shiny Onix flees too, any the group find a clearing and a way out of the island. Jarvis reminds them of being careful at such places. They all return back to Cynthia's villa.