Pokemon Sun & Moon

Synopsis

Rockruff, now close to evolving, goes off on its own during the night and encounters Akala Island guardian Tapu Lele. Rockruff battles Tapu Lele but is easily defeated. Concerned for Rockruff, Ash and Pikachu chase after and find Rockruff, but Rockruff attacks Ash and, immediately ashamed, runs away. The next day, everyone else joins in the search for Rockruff, including Olivia's Lycanroc. Rockruff, injured after falling into a river, is found by both Olivia's and Gladion's Lycanroc and brought to the Ruins of Life. Ash arrives with Olivia and Professor Kukui in time to stop the Island Guardian from battling the two Lycanroc. Using energy from Ash and both Lycanroc, Tapu Lele heals Rockruff, who then evolves into Dusk Form Lycanroc.

(Source: Wikipedia)