TV-Series
Description
Mr. Heartland serves as a secondary antagonist throughout the Yu-Gi-Oh! ZEXAL anime. He is introduced as the charismatic and benevolent-seeming mayor of Heartland City, a public figure who presents himself as a cheerful government official deeply invested in the well-being of his citizens and the success of events like the World Duel Carnival. This warm and flamboyant persona, complete with stage costumes and the catchphrase Heart Burning, hides a cruelly manipulative and deceitful true nature. Beneath the public smile lies a cunning individual who enjoys the suffering of others and is willing to use any underhanded method necessary to accomplish his goals, showing particular annoyance when anyone disrespects him by calling him an old man.

Mr. Heartland's primary role is that of the right-hand man and chief lieutenant to the main antagonist Dr. Faker. He is responsible for relaying Dr. Faker's orders to Kite Tenjo and overseeing the collection of the powerful Number cards. To facilitate this, he masterminds the World Duel Carnival, a city-wide tournament designed to lure duelists in possession of Numbers to a single location, allowing Kite to systematically hunt them. His motivations are almost entirely aligned with Dr. Faker's initial scheme, which involves using Hart Tenjo's powers and the Numbers to destroy the Astral World. He is a willing and zealous participant in this plan, showing no moral hesitation. Unlike Dr. Faker, whose twisted actions are ultimately motivated by a desire to heal his son, Mr. Heartland displays a more purely malevolent streak, showing no concern when Hart is harmed and treating the child soldiers under his command as disposable tools.

Throughout the early part of the story, his relationship with Kite Tenjo is one of constant manipulation and blackmail, continually reminding Kite that his little brother Hart's survival depends on their success. He also acts as a mentor and handler to other agents like Dextra and Nistro, having recruited them from a harsh background as orphans. His authority is demonstrated during the World Duel Carnival, where he acts as the flamboyant master of ceremonies, commentating on duels and even actively manipulating the playing field, such as adjusting a Field Spell card to give his favored duelist Nistro an advantage. Near the climax of the first series, during a raid on Heartland Tower, Mr. Heartland confronts Kite and his friends on a flying platform. A power failure causes him to fall into a portal, sending him not to the Astral World, but to the Barian World.

His character undergoes a significant transformation in the sequel series, Yu-Gi-Oh! ZEXAL II. Found floating in the Lake of Ill Omen, he is rescued by the Barian lord Vector, though his form has degraded into that of a small, fly-like creature. In this state, he retains his head and personality but is physically weak. Out of gratitude for his rescue and fear of Vector's anger, Mr. Heartland becomes a loyal servant to the Barians. He uses his extensive knowledge of the human world, such as the locations of portals between dimensions, to aid their cause. Later, he is restored to a more powerful humanoid form by the god-like Don Thousand and appointed as the leader of a group called the Fearsome Four. In this capacity, he becomes a more direct antagonist, using his newfound Barian powers to confront the protagonists. As a member of the Fearsome Four, he wields a deck and abilities themed around insects, reflecting his transformed state, and uses powerful Barian powers, including the ability to summon a Barian Field spell that halves an opponent's Life Points upon activation.

Throughout the anime, Mr. Heartland demonstrates several notable abilities. Beyond his skills in the Duel Monsters card game, where he is shown to be a formidable strategist, his most prominent ability is his duplicitous nature, enabling him to orchestrate large-scale events like the World Duel Carnival. As a duelist, he is associated with insect and heart-themed cards. After his transformation, his Barian powers grant him supernatural abilities, including teleportation, firing swarms of destructive insects from his staff, and the use of the devastating Emblem of Don Thousand to drain his opponent's Life Points. His journey from a respected city mayor to a monstrous insect-like servant makes him a uniquely recurring and versatile antagonist, whose duplicitous nature remains consistent even as his physical form and allegiances change.