TV-Series
Description
Alexander Rosewater serves as the primary antagonist, holding the position of chairman for the Paradigm Corporation, the ruling entity that governs Paradigm City. As the officially recognized son of the city's founder, Gordon Rosewater, he has inherited immense wealth and authority, which he wields with a sense of absolute entitlement. He is a man in his early forties who dresses in a pristine white suit, a deliberate visual contrast to the black attire of his adversary, the negotiator Roger Smith.

His personality is defined by a deep-seated contempt for those he considers beneath him, including the poor and any foreigners residing outside the city's protective domes. He regards the inhabitants outside the domes as an "abominable mess" and views the city's catastrophes as opportunities for "cleaning." Despite his cold and ruthless approach to governance, which allows him to order the elimination of anyone who threatens his interests, he possesses a distinctly childish and self-centered core. He refers to his father as "Papa" and uses the personal pronoun "boku," which conveys a sense of boyish informality. This immaturity manifests in his treatment of immense power as a plaything, such as crafting a miniature remote-controlled version of the megadeus Big Fau.

Alex Rosewater's primary motivation is an unquenchable thirst for control, not just over the city, but over the power of the megadei, specifically the "Big" type units. He believes the pilots of these machines are "agents of the power of God" and is determined to claim that divine authority for himself. His goal evolves from corporate domination to a messianic complex, where he believes he is destined to become the god of a new world, destroying anyone he deems unworthy, including the people outside the domes and the Union, a foreign power.

In the story, Alex is the ultimate embodiment of the city's ruling class and the primary obstacle for Roger Smith. He initially observes events from his position of power but becomes directly involved when he reconstructs and claims Big Fau as his own. He treats the megadeus as a tool to enforce his will, believing his heritage makes him the rightful "Megadeus Dominus." His role becomes that of a tyrannical god, seeking to erase the city's past and rebuild it in his own image.

Key relationships define his character. His relationship with his father, Gordon Rosewater, is central to his psychology. While he claims to love his "Papa," he is also driven by a deep-seated inferiority complex, feeling he cannot live up to his father's legacy. This resentment ultimately drives him to attempt to kill Gordon. His relationship with Roger Smith is one of envy and rivalry. He resents Roger for acting as a god in a city he considers his own and believes there is no room for two such figures. He sees Roger's role as the pilot of Big O as a direct challenge to his own perceived destiny. He also has a pragmatic yet volatile relationship with subordinates like Alan Gabriel, whom he uses for espionage and dirty work.

Over the course of the series, Alex undergoes a noticeable descent. He moves from a calculating corporate villain to an unstable, megalomaniacal figure fused with his own machine. After Big Fau initially rejects him as its true pilot, displaying the message "Ye Not," he forcibly rigs the megadeus using the android Dorothy Wayneright's memory core. Once he re-enters the cockpit, his mental state rapidly degrades. In the final conflict, he demands more power from Big Fau, which responds by fusing cables into his back, absorbing him into the machine. Though he survives a devastating attack, he is ultimately erased from existence by the arrival of a fourth Big, Big Venus.

In terms of notable abilities, Alex possesses no physical superpowers. His abilities are rooted in his political and corporate authority, which gives him control over Paradigm City's resources, military police, and information. His primary source of power is his role as the pilot of Big Fau, a powerful megadeus. However, his connection to it is shown to be unnatural and parasitic, relying on external components and eventually consuming him rather than being a symbiotic partnership.