A 6th grader who possesses the Metal Breath, a device used to summon and operate with Metal Cardbots. It recognizes Metal Cards to materialize the bots, serving as a vital link between humans and Metal Cardbots. He also uses the Metal Breath to initiate combat and utilize the bots' powers. Jun is bright and energetic. He has a strong sense of justice and cannot ignore people in trouble. Highly curious and proactive, he is often the first to step forward in dangerous situations. He deeply values his friends and comrades and possesses the persistence to never give up easily. He speaks naturally and comfortably like any boy his age. He uses casual speech and jokes around with friends, but becomes calm and firm in serious or dangerous moments. He treats Metal Cardbots as trusted partners rather than subordinates.

A police car Metal Cardbot who is always the first to step up in a crisis. As a Star Guardian, he uses a calm and composed tone. He tends to prioritize logic over emotion and speaks only when necessary. During battle, his speech is firm and powerful. His attitude shows great respect and trust for Jun. He has a strong sense of responsibility and justice, a spirit of self-sacrifice, and absolute faith in his comrades. He has a strong desire to protect people. He often shows an eccentric side. While generally bright, he is dead serious during missions. He possesses high mobility, excellent judgment, and situational awareness, specializing in rescue and pursuit. He excels in close-quarters combat and marksmanship, and is strong at defense and protecting allies. He also possesses excellent leadership skills to guide the team.

A large truck Metal Cardbot characterized by immense strength and superior defense. He is reliable and fiercely loyal. A dependable type who puts his comrades first. He uses a giant hammer to deliver powerful melee attacks, serving as the team's sturdy shield.

An ambulance Metal Cardbot whose role is to save people and heal comrades. He is gentle and deeply considerate, valuing life and safety over fighting. He speaks in a calm, soft tone, always sounding worried about others and trying to reassure them.

A fire truck Metal Cardbot with powerful combat abilities involving flames. He is passionate and has a strong sense of justice. Ironically, he is a bit afraid of fire, which contributes to a hot-blooded personality that can't stand injustice. However, he values his comrades and is highly responsible. He speaks with confidence and energy, honestly expressing his emotions. In battle, he uses a heated and spirited tone.

A small plane Metal Cardbot specializing in high mobility and aerial combat using his small frame. He is playful and mischievous, fearlessly facing opponents much larger than himself. His tone is light and jokey, often teasing others or cracking jokes. However, in combat situations, he shows quick judgment and a serious side. He is the shortest among the bots.

A pirate ship Metal Cardbot and the captain of the Black Gang. He floats in the air when in ship form. He is charismatic, confident, and loyal to his crew. Occasionally, he shows a clumsy or eccentric side. He uses the boisterous and dignified tone of a sea captain, leading Buffalo Crush and Buster Gallon with great strength and leadership. In his transformed state, he is about 10 meters tall. He has a bad relationship with Heavy Iron and is constantly at war with him. He has not yet been sealed.

A monster truck Metal Cardbot who is a subordinate and comrade to Black Hook. He calls Black Hook "Captain." While very strong and rough, he is loyal and follows Black Hook faithfully. His speech is coarse and simple, using a boisterous tone that reveals his dim-witted nature, strength, and confidence. He often eats electricity because he's hungry. He has not yet been sealed.

A tank Metal Cardbot who is a comrade and subordinate to Black Hook. While he possesses strong combat power, his primary trait is his talent as an inventor who creates new machines and devices. He is curious, sly, and takes great pride in his inventions. He has a unique way of speaking, using polite language with everyone, maintaining a relaxed and oily atmosphere. He has not yet been sealed.

A container truck Metal Cardbot. When transformed, he stands at a massive 18 meters, making him a top-tier outlaw with the greatest strength among all Metal Cardbots. He is a dangerous entity who follows no rules or order, acting as he pleases and suppressing opponents with overwhelming brute force and destructive power. He is serious, cynical, and extremely proud, hating to be ignored. His voice is low, heavy, and cold, creating an atmosphere that pressures his opponents. He is frequently at war with Black Hook. He has not yet been sealed.