Main •
Jun Grant () : ::A young blue-haired boy who enjoys being a hero and is an avid
bmx enthusiast. The main wielder of the Metal Breath, Jun, for all of his immature, hot-headed, and selfish behavior, is kind-hearted and always strives to help those in need and make new friends, though he doesn't tolerate actively malicious people. He is the primary human character of the series. •
Blue Cop () : ::A blue, white, and yellow Cardbot who in all forms transforms into a
police car. A member of the Star Guardians - the premier security team of the Cardbots' homeworld - Blue Cop puts on a stoic facade but is as fallible as Jun in multiple instances. He gets upgraded into
Blue Cop S in the second season and
Blue Cop W in the third season, and in the first and second seasons gains the ability to become
Ultimate Blue Cop, formed from combining the powers of 10 other Cardbots (which has 4 metal cards that become two gauntlets and boots), and
Blue Cop Trinity, where he combines with an APC and a prisoner transport bus (which has a greatsword that can transform into a rifle). His metal card weapon in his default forms are all large gauntlets with wrist-mounted cannons, with his subsequent upgrades supplementing these with additional armor for his chest.
Teo () : ::A short, young bespectacled boy who is Jun's best friend. Notably more book smart and well-read than Jun, Teo is much more reclusive than him and was originally alone until Jun offered his hand at friendship. He was the second human after Jun to be let into the Cardbots' secrets in his group.
Anna () : ::A young, pink-haired girl and Jun's love interest. The daughter of Jack, Motown's mayor, Anna is kind-hearted and goes out of her way to help others whenever possible. While she does occasionally find Jun's antics tiresome, she still cares for hin when the chips are down, and was the fourth of his friend group to be let in on the Cardbots' secret.
Edo () : ::A muscular man and the first human other than Jun to be let in on the Cardbots' existence. The owner and sole staff member of his own
auto shop and surrounding
junkyard, Edo prides himself on his handiwork and does not enjoy seeing any damage done to either his equipment, his property, or especially his friends. He is the only adult human in the primary cast, originally being wary of the Cardbots before accepting them upon learning of their species-wide
refugee status. Since then, he has become the default repairman for Jun's group of Cardbots.
Secondary Crest ::A young teal-haired boy and the son of two major scientists. Incredibly gifted, savvy, and intelligent thanks to the resources at his disposal, Crest retains a polite demeanor and is extremely kind-hearted and willing to help. Despite not wielding a Metal Breath, Crest initially held custody of the Cardbot Wild Guardy and assisted him in his goals of claiming Jun's, though after a series of confrontations, Crest handed him over to Jun, but remains a staunch ally. Most of his subsequent appearances involve using his resources to investigate Cardbot-related cases and report to Jun for extra help.
Sebastion ::A maroon and cream-colored monowheeled
butler robot assigned to care for Crest by his parents. As such, he regularly follows his commands while serving to keep him safe.
Peruru ::Introduced in the second season; a young girl from Porcaca island who is descended from Mukara, an ancient tribesman who befriended the crew of the Cardbot starship
Speranza when it crashed several centuries ago. A determined young girl with a strong sense of responsibility, Peruru would prove to be just as kind-hearted and energetic as Jun, eventually joining his group after leaving Porcaca to recover the recently-stolen
Speranze Cardbots. Originally armed with Mukara's spear, Peruru was unable to use his Metal Breath until the final battle against Flame Nova. ==Episodes==