Jixtus's plan was a plot, created by the Grysk "Jixtus," to destroy the Chiss Ascendancy by drawing the Ascendancy into civil war that would weaken the Ascendancy to a state where the Grysk Hegemony could easily conquer it. Jixtus dispatched Haplif and other agents to learn about the culture of the Chiss and how they could manipulate ambitious officials into igniting and escalating armed conflicts. Jixtus' key to destroying the Chiss Ascendancy would turn out to revolve around the Chiss family, and how family politics dominated many aspects of Chiss society.
Haplif and other agents of Jixtus were dispatched to pose as "cultural nomads" within Chiss space, where they would learn the weaknesses of Chiss society and attempt to exploit them. The agents successfully convinced officials of three Great Families to declare family emergencies, marshaling their personnel from the military to staff their family fleets to seize control of a world supposedly rich in the valuable metal nyix. Unbeknownst to the Chiss involved, the fabled "Agbui mining world" was in fact "a worthless rock."
The three Great Families manipulated into almost attacking one-another were the Xodlak, the Erighal, and the Pommrio families. Each of those Great Families was allied with a different Ruling Family, and conflict between the Great Families would spread to the Ruling Families and eventually the entire Ascendancy. Jixtus hoped that the Ascendancy would sufficiently weaken itself for it to be easy for the Grysk Hegemony to conquer. However, Jixtus and Haplif's plot was foiled by the actions of a rancher named Lakphro and Senior Captains Thrawn and Lakinda.
Around the end of the Clone Wars, Haplif was sent by Jixtus to instigate a disastrous civil war among a species native to a world rich in nyix. That war devastated the planet and its people, and led to the death of most of its population. The Agbui subsequently colonized that planet and mined it for nyix, including the nyix brooches they would come to use in the plot to destroy the Chiss Ascendancy. However, a group of around 200 refugees fled the planet to Rapacc, hoping to find the fabled noble warrior people known as the Chiss to protect them against evil. Haplif, unable to signal Jixtus due to the lack of a communications triad on Sunrise, contacted the Nikardun Destiny and told them that the refugees were raising an army against Yiv the Benevolent. Thus, Haplif indirectly cause the Nikardun blockade of the Rapacc system and Thrawn's subsequent discovery of the Nikardun as a threat.
Two months after the defeat of General Yiv the Benevolent of the Nikardun Destiny, Jixtus captured the Pathfinder navigator Qilori of Uandualon somewhere deep in space. Jixtus both threatened and enticed Qilori to join him in his nascent plot against the Chiss, against whom Qilori sought revenge. Qilori joined Jixtus in his plot. Jixtus and several other agents of the Grysk Hegemony had predicted that the Nikardun efforts against the Chiss would fail, and thus prepared a more discreet approach to conquering the Chiss from within.
After months of living among the Chiss posing as "cultural nomads," Haplif learned of an ambitious Xodlak family Councilor named Lakuviv he would come to manipulate into lighting the spark that was to lead to a Chiss civil war. Haplif convinced Lakuviv, Councilor of Celwis's Redhill province, that the Agbui were in a possession of a world rich in the valuable metal nyix used in starship armor, and that his people were not aware of the value of the "abundant" nyix he claimed they possessed. Haplif and his fellow Agbui intended to give gifts of nyix jewelry to ambitious elites and sell such jewelry for deflated prices to pique Lakuviv and others' interest in seizing control of the source of the nyix.
Lakuviv sent his Senior Aide Lakjip to the Agbui's purported mining village on Hoxim, where she confirmed that she believed the Agbui to possess an abundance of the precious metal. After Lakjip returned from Hoxim, Councilor Lakuviv carried out a coup against Celwis's Xodlak Patriel Lakooni and impersonated her to declaring a Xodlak family emergency. He used her emergency powers to assemble the Xodlak fleet to stake a claim to Hoxim for the Xodlak, which he believed would secure the Xodlak a return to the Ten Ruling Families and himself a promotion to the rank of Cousin.
Similar plots were conducted at the same time with the Erighal family on Copero and the Pommrio family on Sarvchi, resulting in each of those Great Families declaring family emergencies and assembling their fleets to seize the fabled "Agbui mining world," which was in fact "a worthless rock."
Each of the Great Families strung into the plot were aligned with a separate, mutually-rivaled Ruling Family. Conflict between the Great Families would spread to their allied Ruling Families, and then the entire Ascendancy. The alliances the Grysk hoped to exploit were:
Once the Ascendancy had entered began to fight itself, Jixtus and Nakirre planned to travel to Csilla with Jixtus's fleet and the Kilji war cruiser Whetstone, where they would annihilate the Chiss government.
The family fleets of the Xodlak, Erighal and Pommrio families arrived around the same time above Hoxim, where each attempted to stake a claim to the planet and its mines for their respective families. The families were clearly willing to fight to the death over the resources, when they discovered the Springhawk nearby and apparently under attack, derelict, and in need of rescue.
The plot was prevented from succeeding at the Hoxim incident, where Senior Captains Mitth'raw'nuruodo and Irizi'in'daro convinced the three manipulated Great Families to cooperate to "rescue" Thrawn and his Springhawk. The supposed nyix mine was destroyed in the battle, preventing the Families from fighting over it.
The plot to destroy the Chiss Ascendancy, together with certain Chiss individuals' response to it, serves as the main plot of Timothy Zahn's 2021 novels Thrawn Ascendancy: Greater Good and Thrawn Ascendancy: Lesser Evil. The plot was first alluded to via a promise from "Jixtus" to Qilori in Greater Goods 2020 prequel, Thrawn Ascendancy: Chaos Rising.