Zill Kartay was a male Neimoidian consul within the ranks of the Trade Federation. During the events of 32 BBY, following the successful invasion of the planet Naboo by the Trade Federation, he was selected to serve on the Occupation Council that governed the occupied world, establishing his presence in the planetary capital of Theed. After Naboo was liberated by its Human and Gungan populations, Kartay, along with the remaining members of the council, faced arrest and were transported to Coruscant, the central world of the Galactic Republic, to be held accountable for their actions.
In the closing decades of the Galactic Republic, during the time of Supreme Chancellor Finis Valorum's leadership, there existed a male Neimoidian species member named Zill Kartay. He held a position within the Trade Federation, a complex network of trade officials and related administrators. As a Federation consul, he was given ambassadorial responsibilities on a worlds or territory belonging to the Federation. In 32 BBY, the Trade Federation, acting under the orders of Darth Sidious, a mysterious Dark Lord of the Sith, launched an invasion against the remote planet of Naboo. On this occasion, Consul Kartay went with Viceroy Nute Gunray to Naboo's capital city of Theed, where he became a member of the so-called Occupation Council. Kartay's fellow council members included Gunray, his aide Settlement Officer Rune Haako, Magistrate Kund Ekorr, Treasurer Hap Brehg, and Chronicler Viff Almay.
While the Theed Royal Palace hosted the Occupation Council's discussions, the Human and Gungan inhabitants of Naboo chose to put aside their differences and collaborate to reclaim their planet. As a battle loomed in the nearby Great Grass Plains, Kartay and the other councilors remained within the relative safety of the Theed palace throne room, believing themselves secure. Following a hard-fought struggle both on the ground and in space, the rebellious locals managed to destroy the Federation's droid army. Simultaneously, an elite team led by Queen Amidala, Naboo's rightful ruler, infiltrated the palace to apprehend the Neimoidian dignitaries. In the aftermath of the battle, Captain Panaka of the Royal Naboo Security Forces arrested Kartay, along with his fellow councilors Ekorr and Brehg. Subsequently, he and his colleagues were transported as prisoners aboard a shipped to the Republic capital of Coruscant to await their trials.
Zill Kartay made an appearance as an unnamed background character in the film Star Wars: Episode I The Phantom Menace, which premiered on May 19, 1999. However, considering the Occupation Council's collective appearance in Terry Brooks's novelization of the movie, released a month prior, Kartay's actual debut can be traced back to April 21 of the same year. In 2014, his name was officially revealed in Rogues Gallery: The Devious Neimoidians Revealed, an article penned by Tim Veekhoven, Kevin Beentjes, and Sander de Lange for the Star Wars Insider magazine's 147th issue. Kartay's name was chosen in honor of Lizzi Kartay-Dod, a Neimoidian fan known as Kweh-chan on the online Star Wars encyclopedia Wookieepedia.