Zeda commands as Supreme Commander of the Illumidus Earth Occupation Forces after Earth's conquest, holding ultimate authority over planetary administration and military operations. He holds genuine respect for Captain Harlock's combat abilities and military record, acknowledging him as a formidable adversary despite their opposition. This respect prompts Zeda to personally intervene, stopping his subordinate Murigson from assaulting Harlock during their initial meeting at Occupation Headquarters. Seeking to recruit Harlock for the Illumidus regime, Zeda offers him command of an Earth Volunteer Army to attack and destroy Tokarga. This operation forms part of a broader Illumidus strategy to eliminate Tokarga, deemed no longer useful, reflecting their pattern of discarding conquered worlds. Through interactions with Earth's collaborationist leader, Prime Minister Triter, Zeda utilizes local authorities to enforce Illumidus rule and achieve objectives like the Tokarga subjugation. When Harlock rebels and escapes Earth aboard the Arcadia to aid Tokarga, Zeda orders the execution of Emeraldas and Maya in retaliation and to force Harlock's surrender, demonstrating his willingness to employ extreme measures against resistance. During Harlock's return to Earth, Zeda personally confronts him, initiating a ship-to-ship duel that reveals his preference for direct military engagement against a worthy opponent. Defeated in this duel, Zeda accepts the outcome with honor, expressing a mutual desire to one day share a toast with Harlock "in Hell," acknowledging their complex adversarial relationship. His character blends pragmatic militarism with a personal code of honor, evident when he allows Harlock to leave Earth without further pursuit after their duel. He maintains authority over aggressive underlings like Murigson, permitting their tactics but withdrawing support when they act without orders, as seen when Murigson attempts an unauthorized ambush on Harlock. Zeda philosophically justifies the occupation and the Tokarga operation as necessary for Earth's survival through cooperation, framing his actions as vital for planetary security despite their morally compromising nature.