Custard is the pilot of the Zoomer and takes the Save-Ums on the adventures.
- Age: 4 years old
- Birthday: December 6
- Favorite Color: Purple
- Favorite Food: Egg rolls, popsicles, pure honey on a spoon.
- Likes: Anything with wheels!
- Dislikes: Inappropriate things, troublemakers.
- Personality: Excitable, enthusiastic, imaginative.
- Secret Wish: To sneak around invisible and spy on people.
- Special Talent: Trampoline bounding and finding lost stuff.
- Learning How To: Remember his dreams and tell his friends.
Custard is 4 years old. His imagination is as big as the sky! As big as a baby dinosaur! As big as the moon! Well, you get the idea.
Custard has a very active imagination. Custard applies his creativity to everything he does. When Custard is in the house, the potential for play goes through the roof and the everyday becomes fantastical.
Custard's approach to using gadgets is often very clever, and his enthusiasm for experimentation is truly inspiring. Once Custard starts to think "outside of the box" a full-on Save-Ums brainstorm always ensues!
Custard is excitable, enthusiastic and imaginative.
Coco (LunatheSaveUmsFan style)
Among the rest of the Rivera family, Custard stands out by his love and passion for music. However, because of the generation-spanning taboo his family has towards music, he must keep this side of himself hidden. The only ones who are aware of his passion are his elderly great-grandmother Matilda and his dog Kipper. At the beginning of the film, Custard is encouraged to play music by a mariachi only for the mariachi to get scared away by Miss Crawley, but not before informing him of a music contest being held on Día de los Muertos. Though Custard inquires about the family's past that motivated his great-great-grandmother to ban music, Miss Crawley refuses to talk anymore about the subject on Custard's great-great-grandfather.
In his hideout, Custard has a shrine dedicated to his musical idol Eduardo Perez (AKA El Macho). Viewing the films while perfecting his makeshift guitar, the voice of El Macho inspires Custard to follow his dreams. On his way to the contest, Custard narrowly evades Miss Crawley and his parents from finding his guitar just as Miss Crawley declares him ready to join the family's shoemaker business. Custard feigns excitement to get Miss Crawley and his parents to leave. But right after, Kipper causes the ofrenda to shake, where the photo of Custard's great-great-grandparents falls off and shatters. After Custard notices in the picture that his great-great-grandfather holding the guitar of El Macho, he concludes that El Macho is his great-great-grandfather and decides to enter the contest to become a musician. Announcing this to the Rivera household, Miguel's family tries to convince him to give up the idea, fearing such a dream would lead Custard to end up like his great-great-grandfather. Miss Crawley confronts him personally to make him choose between family and his dream; when Custard still stands firm for music, Miss Crawley angrily destroys his guitar.
Frustrated yet undeterred, Custard runs off to enter the contest. However, since he needs an instrument to enter, he (reluctantly) enters El Macho's mausoleum and takes his guitar. Alone with the guitar, Custard apologizes to El Macho and explains his reasons for taking the instrument. Before heading out, he gives the guitar a strum. This causes marigold petals surrounding him to light up, and Custard overhears people coming to the mausoleum. Custard tries to come clean, but he discovers that he can't interact with the living people. As Custard begins to panic, he sees several deceased spirits moving around the cemetery.
Fearing his situation, Custard is suddenly greeted by Kipper, who somehow still sees him. Kipper then runs off and leads Custard to the deceased members of his family. They understand Custard's situation and take him to the Land of the Dead to help him. At the Grand Central Station, Custard meets his great-great-grandmother Pururu, who was unable to cross over due to Custard knocking off her picture on the ofrenda. The family learns that Custard had a curse placed on himself for stealing the items of the deceased, which turned him into an incomplete spirit. If Custard is still in the land after sunrise, he will become a spirit and remain trapped in the land forever. When they learn that to break the curse a member of his family must give him their blessing, Pururu tells him she will give him her blessing if he gives up music. Custard reluctantly agrees and is immediately transported back into El Macho's mausoleum. Spotting the guitar back on its hooks, Custard attempted to take it only to be returned to the Land of the Dead two seconds later for breaking his promise. Pururu demanded that he adhere to her wishes but Custard refuses and runs off to seek his great-great-grandfather instead, believing him to be El Macho.
He enlists Leo Kyoranne's help after he hears that he knows El Macho. Leo agrees to help him if he puts his picture on an ofrenda when he gets home to which Custard agrees. To help blend Custard in, Leo disguises Custard as a skeleton with facepaint, and they head off to find El Macho. The pair hear about a contest where the winner will get to meet El Macho. After they get Custard a guitar, Custard performs in the contest. However during the contest, the deceased Riveras show up. Leo confronts Custard about this as he lied and said El Macho is his only family. This makes Custard ditch Leo and Kipper to go find El Macho himself. Custard escapes Pururu and her alebrije Loftwing by running into an alleyway, and Pururu tries to stop him by revealing that she didn't ban music because she hated music, but because she loved her family more and wanted to raise her daughter Matilda. However, Custard isn't moved and continues toward El Macho's mansion. After the winners of the contest get him inside, Custard gets his idol's attention by singing a song. He tells El Macho he's his great-great-grandson and that he needs his blessing so he can go home. El Macho agrees, but before he can give it Leo show up to remind him of their deal.
Leo reveals that he wrote all of the songs El Macho is famous for singing. When Leo says El Macho once said he would move heaven and earth for him, Custard points to one of El Macho's films where the villain says the same line while poisoning El Macho's character. Leo remembers his last night alive out loud and suddenly accuses El Macho of poisoning him. After the Boos from the Mario series take him away, El Macho asks Custard if he thinks Leo is right. Custard tries to assure him he doesn't but enough of the doubt oozes into his voice to alert El Macho to the fact that he does. El Macho tells his guards to take Custard away too. Custard protests that he's his family to which El Macho coldly says that Leo was his best friend. Custard realizes that Leo is right to which El Macho tells him one must be willing to do what it takes to seize their moment.
Boos throw Custard in a ceneto, where Custard finds Leo there with him. While lamenting, they learn that Leo is Custard's real great-great-grandfather. Soon, they are saved by Kipper and the other Riveras. Custard then realizes that Kipper is his spirit guide, which allows Kipper to assume his true alebrije form. After regrouping with the rest of the family, Custard tells Pururu what really happened to Leo. While Pururu still holds hostility toward Leo, she agrees to help as Matilda is losing her memory of Leo.
Together, they infiltrate El Macho's concert and get Leo's photo back. Pururu and Leo prepare to send Custard back with the photo with no additional conditions, however El Macho interrupts the blessing to drop Custard from the building. The deceased Riveras plead with El Macho to see reason, but El Macho is too fixated on remaining famous to give Miguel mercy. Noticing his family turn the cameras on behind El Macho's back, Custard calls El Macho a coward to which El Macho's retorts that he's the greatest musician in the world. Custard angrily retorts "Leo is the real musician! You're just the guy who murdered him and stole his songs!" El Macho shamelessly declares he'll do what he must to remain famous and he drops Custard from the building. Kipper tries to save Custard from plummeting but Custard is too heavy, and Leo's photo slips away from Custard mid-fall. Fortunately, Custard is saved by Loftwing at the last minute, while El Macho's crimes are exposed to the audience. At that moment, sunrise approaches as Custard nearly completes his transformation to a spirit. Although Pururu implores Custard to take the blessing for Leo's sake, Custard refuses to leave Leo as the latter starts to fade away, but he is forced to accept Pururu's blessing in order to save him and Matilda.
Awakening back in to El Macho's mausoleum, Custard, with Leo's guitar in hand, immediately runs back home. Once home, Custard finds Matilda catatonic, having lost most of her memory. Heartbroken to see his great-grandmother in this state, Custard breaks down to his parents. Suddenly, he remembers Leo's guitar and helps Matilda remember Leo by singing "Remember Me" to her. The song restores Matilda's memories and she reveals the truth of her father to everyone in the family. By the following year, his family have accepted Leo and music, and Custard has a new baby sister named Stella named after his now-deceased Matilda. The film ends with Custard playing the guitar while his ancestors play invisibly beside him.
- Custard's voice actor is Jordan Francis in the series, but in the reboot, he is voiced by Lenore Zann (who voiced Island Owl), making him sound the way he sounded in Season 1.
- In GoAnimate, his voice is Jennifer.
- Custard had his vehicle, which is the Zoomer.
- His name in Japanese is カスタード.
- In the French dub, his name is changed to Berlingot.
- In the Spanish dub, his name is changed to Jelly.
- In the Brazilian and European Portuguese dubs, his name is changed to Sagu.
- His catchphrase is "Bam!"
- Custard says the word "cool" a lot of times constantly.
- Custard has his werecat form (that happened in the Save-Ums! Unleashed manga part Custard becomes a werecat)!
- His signature sound-based attack is Guitar Attack (just like Zora Link and Barbara the Bat).
- Jordan Francis - English
- Rie Kugimiya - Japanese