These Jangmo-o first appeared along with Hakamo-o and their leader, Totem Kommo-o. When Lillie and Gladion tried to get to The Altar of the Sunne, the Jangmo-o and Hakamo-o prevented the two humans from going any further. After Totem Kommo-o showed up, Lillie and Snowy battled the Jangmo-o and Hakamo-o, attacking them with Powder Snow, while Gladion and Silvally dealt with Totem Kommo-o. When Gladion was about to equip Silvally with a Fairy-type Memory Disc, one of the Jangmo-o disarmed him, and the Memory Disc land's underneath Totem Kommo-o. Jangmo-o and Hakamo-o attack again, but are stopped by Snowy's Powder Snow, then freezes the ground, letting Gladion and Silvally skate across the Jangmo-o and Hakamo-o with ease. They only watch as Gladion equips Silvally with the Memory Disc and Silvally defeats their leader with Multi Attack.
They along with Hakamo-o reappeared in Revealing the Stuff of Legend! where they attacked Professor Burnet and her Munchlax. Professor Kukui and his Braviary came to their rescue, and Braviary knocked all of them out with a single Brave Bird.
None of Jangmo-o's moves are known.