Henry, whose real name is Hikaru Agata, is a prominent character in the Medabots franchise who operates under several different identities throughout the story. By day, he works as a clerk in a convenience store, but he is also the mysterious masked thief known as the Phantom Renegade and the powerful robattling champion called Space Medafighter X. He is a young man, approximately twenty-one years old, with a calm and knowledgeable demeanor that comes from years of experience as a Medarotter.

The character has a deep and tragic background that shapes his actions. Approximately ten years before the main events of the anime, Henry was a young champion who reached the World Robattle Championship with his original partner, a Medabot named Metabee. However, during that tournament, a catastrophic event known as the Ten Days of Darkness occurred, during which a rare medal caused every Medabot in the world to go berserk and attack humans. Henry was forced to make the devastating decision to destroy his own Medabot and its medal to stop the rampage, an event that took ten days to resolve and left him with lasting guilt. The medal was eventually repaired, but the original Metabee lost all memories of their time together. This traumatic experience drives Henry to take extreme measures to prevent such a disaster from ever happening again.

Henry's motivations are rooted in this past tragedy. As the Phantom Renegade, he dedicates himself to stealing and protecting rare medals that could potentially trigger another catastrophic event similar to the Ten Days of Darkness. He works in secret, often alongside Dr. Akihabara, to keep dangerous medals out of the wrong hands and maintain a fragile peace in the world of robattling. Despite his methods being illegal, his intentions are ultimately selfless and protective. Later, he adopts the persona of Space Medafighter X to compete openly in tournaments, using this platform to continue his mission while remaining hidden from authorities who seek the Phantom Renegade.

In the story, Henry serves as a mentor and guide to the protagonist Ikki Tenryou. Significantly, he is the one who sells Ikki the parts for his own Metabee, an older model that was once Henry's own partner. He also, in his Phantom Renegade guise, provides the rare medal that brings Ikki's Metabee to life, setting the young Medarotter on his journey. This connection creates a symbolic passing of the torch from the former champion to the new generation. Henry maintains several other key relationships, including with Dr. Akihabara, who supports his secret operations. He also has a connection to Kirara, a childhood friend who adopts a similar disguised identity known as Phantom Lady. His relationship with his own Medabot, Arcbeetle, is perhaps his most defining bond, representing the painful past with his original partner and the hope of redemption through their continued partnership.

Henry's personal development is evident in his transition from a celebrated champion to a guilt-ridden loner working in the shadows, and finally to a mentor who finds a measure of peace by helping a new generation of Medafighters. His arc involves learning to confront his past trauma rather than simply trying to prevent its repetition. The guilt over destroying his original partner weighs heavily on him, but through his eventual openness with others and his willingness to fight openly as Space Medafighter X, he begins to heal.

Notable abilities of Henry are linked to his mastery of robattling and his partnership with his Medabot, Arcbeetle. Arcbeetle is a powerful beetle-type Medabot equipped with a legendary Kabuto medal. This rare medal grants Arcbeetle superior reflexes and combat skills compared to standard Medabots. Arcbeetle is proficient in both long and short-range attacks, with his primary weapons including triple-barreled lasers on his arms and a devastating head-mounted attack known as the Prominence. The Prominence channels energy from solar modules to fire a concentrated blast of incredible power, described as wielding the power of the sun. Arcbeetle also possesses the ability to use the Medaforce, an energy-based attack that draws upon the medal's power to fire a powerful laser beam. Beyond these attacks, Arcbeetle is exceptionally fast and agile, able to dodge bullets and even catch seeker missiles despite his size. His medal also contains a built-in communicator that allows him to contact Henry through his Medawatch at any time.