During the wedding of Professor Kukui and Professor Burnet, Lusamine and her foundation invited Ash, Lana, Kiawe, Mallow, Sophocles, and Lillie to join the Ultra Guardians to help deal with future Ultra Beast incidents, which they accepted.
They also have an alternate future counterpart known as the Ultra Rangers. However, an Ultra Beast known as Guzzlord was deemed too powerful for them. They failed to protect Alola from its dystopian destruction. Dia, a member of the Ultra Rangers and one of the region's few survivors, managed to escape and went into hiding. The sudden appearance of Ash and his Pikachu in the Ultra Rangers' universe caused the Shiny Tapu Koko to resurface to aid both Ash and Dia to defeat Guzzlord once and for all, restoring the alternate Alola.
- Ash's Pikachu (formerly)
- Rotom Pokédex
- Ash's Rowlet
- Ash's Lycanroc (Dusk Form)
- Ash's Incineroar
- Ash's Naganadel - released in Securing the Future!, later rejoined in Z-Move Showdown!
- Ash's Melmetal
- Lana's Primarina
- Lusamine's Clefable
- Kiawe's Turtonator
- Kiawe's Marowak
- Mallow's Tsareena
- Sophocles' Togedemaru
- Sophocles' Vikavolt
- Gladion's Umbreon
- Gladion's Lycanroc (Midnight Form)
- Gladion's Silvally
- Meltan - Merge with Ash's Meltan into one Melmetal as of Final Rivals!
Ultra Guardians assisted
Geodude (multiple) *
Graveler (multiple) *
Ultra Guardians befriended
Ultra Guardians watching over
- The Ultra Guardians' suits are identical outside of color differences (for example, Ash wears blue and Kiawe red).
- Ash and Lana both wear blue, but in different shades to differentiate them, with the former wearing more of an indigo.
- The suits are similar to the Sentai uniform worn by the characters in various Sentai series, excluding the Sentai helmets.
- The suit up is also similar to G Gundam's Combat Suit, and the uniforms have a similar suit design as Timeranger's pre-Ranger form Chrono Change suit.
- As the heroes' Pokémon transform into Ultra Guardians, the females are given ribbons while the males are given pendants. However, genderless Pokémon are seemingly random, with Rotom, Naganadel, Silvally, and Melmetal being designated as "male" while Shaymin is designated as "female".
- In her Ultra Guardians' suit, Lillie brings back her ponytail hairstyle.
- Five of the seven ride Pokemon for the Ultra Guardians are Dragon-type, with the exceptions being Kiawe's Charizard and Sophocles's Metang.
- Gladion's uniform being a different design may be a reference to the long-running Super Sentai/Power Rangers series. Many seasons of the series typically have the main characters joined by a "Sixth Ranger" midway into the series. Sixth Rangers typically have their costume differ in design from the core team to make them more distinct.
- When the group is shown on their Ride Pokémon, Kiawe is on what is most likely his usual Charizard while Ash (having previously been on one early into his Kalos adventure) is on a Garchomp.
- Ash himself owns a Charizard and Noivern, even having flown on the former previously, but he is more battle-minded than the Ride Pokémon.
- Each Ultra Guardian Trainer shares the same designs on each two different Z-Ring designs, particularly on each ring, but different colours. Ash's Z-Ring was different before getting an upgrade.
- Ash has captured more Ultra Beasts than any member, with a total of 4.