Pokémon the Series: Sun & Moon Episode 88: Full Moon and Many Arms!
Episode 88 of 146 of Pokémon the Series: Sun & Moon, aired August 30, 2018, 25 minutes. Available with English subtitles and dub where released.
Episode summary
The Ultra Guardians spring into action to protect Lunala from the mysterious creature who has chased it through the Ultra Wormhole!