Ahsi Yim was a Yuuzhan Vong female who belonged to the shaper caste, a group specializing in biotechnology. She utilized her knowledge to support the warriors of the Yuuzhan Vong during their military campaigns. During the Yuuzhan Vong War, she served as her people sought to take over a galaxy, conquer its planets, and force its inhabitants to adopt the Yuuzhan Vong religion. Following the conquest of Duro, Ahsi Yim was assigned to the terraforming process of the planet. However, she realized that the established orthodox protocols for her caste were outdated and inadequate for the task. Instead of strictly adhering to these rules, Ahsi Yim committed heresy by modifying them to better suit the project's requirements. Because her methods remained secret and her work was praised, Yim was escalated to the position of master shaper in 28 ABY and sent to Coruscant, the conquered capital of the New Republic. Yim continued her terraforming work there, encountering similar issues as on Duro and again resorting to secret heretical practices.
Her heretical actions were eventually discovered. However, instead of being sacrificed to the Yuuzhan Vong gods, she was secretly permitted to join a team of shapers working under the clandestine supervision of Supreme Overlord Shimrra. This team was tasked with developing new technologies, even through heretical means, to aid in the ongoing conquest of the galaxy. Ahsi Yim collaborated with her sister, Nen Yim, while also maintaining connections with the Quorealists, a Yuuzhan Vong faction on Coruscant that opposed Shimrra. In 29 ABY, her sister approached her, requesting assistance in arranging a meeting with a Quorealist. Yim facilitated this meeting, but Nen Yim was abducted from the compound shortly afterward. Ahsi Yim was subsequently executed when Shimrra received a rumor that she had been involved in the kidnapping.
Ahsi Yim, a member of the Yuuzhan Vong species, received training as a shaper. Shapers were Yuuzhan Vong scientists who specialized in manipulating their race's biological technology for preservation and survival. After millennia of travel through the Intergalactic Void, the Yuuzhan Vong arrived in another galaxy, believing it to be their new home. Like all Yuuzhan Vong, Yim was taught to believe that their gods had gifted this galaxy to their worshipers.
The invasion of the galaxy progressed successfully, and Ahsi Yim was assigned to terraform the conquered planet Duro. Duro, a world damaged by centuries of technological excess, was captured from the defending New Republic in 26 ABY. The goal was to transform Duro into a lush, green paradise. However, while working on this project, Yim began to notice deficiencies in the shaping protocols, the strict and traditional instructions governing the art of shaping. Instead of following these protocols strictly, Yim risked death by engaging in heretical research. She adapted the protocols to better suit the project's needs, rather than trying to work within the constraints of orthodoxy. Yim's actions went unnoticed, and thanks to the collective efforts of the shapers, Duro was successfully transformed into a world filled with vegetation.
A year after the conquest of Coruscant, the New Republic's capital, Ahsi Yim was promoted to master shaper. She was once again tasked with terraforming a world, this time Coruscant itself. The goal was to remodel Coruscant in the image of Yuuzhan'tar, the Yuuzhan Vong's lost homeworld. Despite significant changes to Coruscant, problems soon emerged after its transformation. The dhuryam, a telepathic Yuuzhan Vong organism responsible for overseeing the newly transformed planet, began to disrupt the terraforming process with various glitches. Ahsi Yim watched with frustration as the shapers responded with conservative, orthodox measures to address these issues, including an itching plague that angered the Yuuzhan Vong conquerors. These widespread problems led to the execution of Master Shaper Ch'Gang Hool for failing to resolve the situation.
Ahsi Yim had already observed how the galaxy's defenders were adapting to the Yuuzhan Vong invasion. Instead of relying on existing technology, they were developing new warships and tactics. Having witnessed the conservatism of the shaper caste, Yim came to believe that adapting the shaping protocols, despite being considered arch-heresy because only the god Yun-Yuuzhan was believed to be able to create new biotechnology, was the only way for the Yuuzhan Vong to survive. She began to practice heresy on a larger scale but was eventually discovered. However, instead of being executed, Ahsi Yim was taken to a secret compound within Supreme Overlord Shimrra's palace on Coruscant. There, she was allowed to continue experimenting with shaping technology under the guidance of her sister, Nen Yim, who had been tasked by Shimrra with developing new technology to combat the galaxy's defenders.
Despite her new role, which allowed her to contribute to the conquest of the galaxy, Ahsi Yim kept secrets. She maintained close ties with the Quorealist underground, a dissident faction of Yuuzhan Vong who opposed Shimrra and remained loyal to his deceased predecessor, Quoreal. She understood that the secret shaping laboratory where she worked was evidence of the failure of orthodox shaping protocols and that Shimrra was concealing this truth from the Yuuzhan Vong. Furthermore, rumors circulated among Ahsi Yim's associates regarding Ekh'm Val, a Yuuzhan Vong commander who had made a chance discovery and lost his life after reporting it to Shimrra. These mysterious circumstances were further complicated when, in 29 ABY, her sister Nen Yim was approached by Onimi, Shimrra's familiar, and given an object to study in secret. Ahsi Yim was intrigued by this delivery, and a day later, she was summoned to Nen Yim's quarters.
There, Ahsi Yim learned her sister's secret. Nen Yim had been ordered to study a mysterious starship with a similar genotype to the Yuuzhan Vong's living starships and to create weapons to counter its biotechnology. The two master shapers discussed the reasons behind Shimrra's orders, which involved the legend of Zonama Sekot, a living planet sighted in the galaxy by Ekh'm Val, who was subsequently killed by Shimrra for his discovery. Ahsi Yim and her sister agreed that it was likely that Shimrra, while wanting to deny the existence of Zonama Sekot to the rest of the Yuuzhan Vong due to the potential danger it posed, was also preparing a military strike against the world. However, the lack of information led Nen Yim to request that Ahsi arrange a meeting with someone who knew about Zonama Sekot and would not report the meeting to Shimrra.
The master shaper realized that a Quorealist would be the ideal candidate and arranged a meeting between Nen Yim and High Priest Harrar of Shimrra's court. Ahsi Yim continued her work in the secret compound, only to be shocked when a pair of Jedi Knights infiltrated the laboratories with the help of rebel Shamed Ones and kidnapped Nen Yim before escaping aboard the mysterious starship. Following Nen Yim's abduction, Ahsi Yim was promoted to lead the shaping project in her sister's place. However, her tenure in this position was short-lived. Shortly after her promotion, she was executed on Shimrra's orders. Qelah Kwaad, one of Yim's colleagues who coveted her position, had deceived Shimrra into believing that Ahsi Yim had aided in Nen Yim's escape.
Ahsi Yim was a young, progressive Yuuzhan Vong who was willing to risk her life to help her species survive. Instead of adhering to the rigid shaping protocols, she secretly experimented with new technologies. Skilled and talented in her work, Yim was assigned to terraform two different worlds and was promoted to master shaper for her efforts. After Nen Yim disappeared from Coruscant, Ahsi Yim was the obvious choice to replace her.
Astute and pragmatic, Ahsi Yim recognized that Yuuzhan Vong orthodoxy had failed her species. She had little faith in the gods or in Supreme Overlord Shimrra, who, while representing the species' orthodoxy, was also secretly undermining it. Yim maintained connections with dissident Yuuzhan Vong and was aware of much of the intrigue and gossip within the halls of power. Despite observing the flaws in her species' leadership and orthodoxy, Yim's primary concern was ensuring the survival of her race.
Ahsi Yim was introduced as a minor Yuuzhan Vong character in Gregory Keyes' The New Jedi Order: The Final Prophecy. While Keyes' novel does not explicitly state that Yim was executed, The Complete Star Wars Encyclopedia, published in 2008, confirmed that this was indeed the case.