Jaxon Cross, known in Japan as Ekusu Kurosu and by his masked alias Blader X or Kamen X, is the central protagonist of the Beyblade X anime and manga. His personal history is rooted in intensive training from a young age. At seven years old, he had already surpassed his master, Ginro, who gifted him the Beyblade Sword Dran as a parting gift. During their final battle, Jaxon's powerful launch caused a piece of the Bey's blue metal coating to chip off. His master explained that this damage was not a flaw but proof of his growing strength, and that the paint would continue to wear away as he became more powerful, turning the Beyblade into a visual chronicle of his journey.

Jaxon began his professional career by joining the elite team Pendragon, where he formed a formidable partnership with a Blader named Khrome Ryugu. Together with their teammate Multi Nana-iro, they became the undefeated champions of The X, a towering structure where Bladers compete to reach the top. Despite achieving the highest honor, Jaxon felt unchallenged and that the battles had lost their excitement. Believing that Beyblading should always be a game and a source of fun, a view that set him apart from many professionals who treated it as a job, he left Pendragon. To start from the bottom and reignite his passion for meaningful competition, he adopted the masked identity of Blader X, concealing his true self to climb the ranks of The X once more with the specific goal of facing his former teammate, Khrome Ryugu, in a serious battle.

Jaxon's personality is defined by his unwavering pursuit of enjoyment in Beyblading. He loves battles and finds genuine excitement in every match, contrasting sharply with those who see blading as a career. Outside of battles, he can appear playful, lazy, or hard to read, but inside the stadium, he becomes a focused and exhilarated competitor, sometimes laughing with joy when pushed to his limits. This drive leads him to relentlessly seek out strong opponents. He is also known for unusual quirks, such as an affinity for experimental sushi and a quick ability to bond with animals. His catchphrase reflects his emphasis on speed and spectacle: he promises to show his opponents something extraordinary or an invisible X.

In the story, after his former team abandons the amateur Blader Robin Kazami following a crushing defeat, Jaxon, as Blader X, approaches him to form a new team. Recognizing that a lone Blader cannot easily ascend The X, he recruits Robin, and together they create Team Persona, named after his masked persona. The team is later joined by Multi Nana-iro, an influencer who crafts and maintains their Beyblades. Jaxon serves as the team's ace, often preferring to let his battling do the talking rather than taking on an organizational leadership role. His most significant relationship is with Robin Kazami, whom he mentors not with strict lessons, but by reminding him that blading is meant to be fun and by helping him regain his confidence. They develop a brotherly bond, often finding themselves in humorous situations. His relationship with Multi is more technical, centered on her expertise in creating and repairing their Beyblades, such as when she builds his new Bey, Dagger Dran. The central and most complex relationship is with his former Pendragon teammate, Khrome Ryugu, whose own skills were honed in his pursuit of Jaxon. Their high-stakes rivalry culminates in a climactic showdown at the top of The X, which ends with Jaxon's victory. After this victory, he finds himself aimless and without purpose, spending his days absentmindedly making unusual sushi, until he is inspired to battle again by a chance encounter with a mysterious new Blader.

Jaxon's abilities are among the most extraordinary in the series, with his launch power measured at an incredible ten thousand. His primary Beyblades are all from the Attack-type Dran line, including his original Sword Dran, the later Dagger Dran, and the powerful Buster Dran. His signature technique is the Xtreme Dash, which uses the gears on his Beyblade's Bit to interact with the X-Celerator Rail in the Xtreme Stadium, generating explosive bursts of speed for powerful attacks. He has mastered numerous advanced variations of this technique, including Double, Triple, and Infinite Dashes for sustained acceleration, and the Buster Dash, which concentrates all his power into a single, devastating strike. These abilities, combined with his immense strength, speed, and philosophy that battling is a game, make him a nearly unstoppable force whose Beyblade can move so fast it becomes invisible to the naked eye.