Operation Sweep, more infamously known as the Azha Massacre, was a genocidal campaign waged against the mining town of Azha under Emperor Geldoblame's orders as a response to their delaying the shipment of various Iron Ores to the Imperial Fortress a year prior to the events of Baten Kaitos: Eternal Wings and the Lost Ocean.
Azha was a town renowned for being the site for the finest Iron Ores in Alfard, which were frequently shipped to the Alfard capital after mining them in the Lava Caves. However, some time within the then-Emperor Geldoblame's tyrannical rule, Geldoblame enacted harsh labor statues that forced the various people of Azha to work in the Lava Caves endlessly, which ultimately took a toil on them as they were left with exhaustion. After several failed attempts at petitioning Geldoblame's administration to relax the harsh statutes regarding the harsh labor conditions, the people of Azha ultimately ended up reducing their sales of the Iron Ores to the Empire by a significant amount in response.
Geldoblame upon discovering their delaying of their ore shipments was left outraged at their rebellion and decided to "spark a little motivation" into working harder and complying with his orders. In response, he gathered his various top officials in the Alfard military, including Lyude and Fadroh, to his throne room, and proceeded to order them to find everyone responsible for the rebellion and execute all of them, as well as ordering them to torch their various homes as a demonstration of exactly what it meant to "provoke [Geldoblame's] wrath". In order to ensure the task got done, he also ordered for the Mad Wolf Unit to be dispatched to Azha at once.
Lyude, however, spoke up, explaining to his liege that the citizens of Azha were only doing their actions because of the harsh labor conditions via policies that Geldoblame enacted himself. Geldoblame was not pleased with Lyude's insubordinate retort and demanded to know "who gave [Lyude] permission to grow a brain". Lyude, realizing he may have angered his liege, backed down in fear, but it was too late: Geldoblame, a known megalomaniac due to past events, then proceeded to enter an angry rant towards Lyude about how, because he was the Emperor of Alfard, that meant his subjects are his slaves and pawns in a bid for power. He then further elaborated by citing examples of how, if he were to request a slab of Torsina meat, his subjects are obligated to find the animal it was made from, slaughter it, and present it to him in whatever means were necessary; if he were to demand an increase in monetary payment to him, his subjects were likewise required to toil on with their work without rest and pay their taxes as ordered by him; and if he were to wage war against another group of people and thus tell his subjects to fight, absolutely everyone in his Empire, from men, to women, to even children if such was desired by him, must take up arms and fight to the bitter end, and cited that such was the sole purpose of existence for his subjects, which he referred to as "mindless weaklings" and even sadistically implied that such was the only reason why he even tolerated their being alive. After the tirade, he then turned to Lyude and angrily called him a fool for attempting to speak out against his orders.
Ultimately, the massacre occurred as scheduled, where they did exactly as Geldoblame ordered, and proceeded to kill over half of the population and left orphans in their wake. Afterwards, the corpses were disposed of in the various flows in the Lava Caves.
The massacre was among the worst crimes committed by the Alfard Empire under Geldoblame, with Savyna, the leader of the Mad Wolf Unit, resigning afterwards out of disgust for having partaken in the massacre, with her bearing immense guilt in her role in the massacre even a year later. In addition, because of Lyude's attempt at speaking out against the massacre, he ended up demoted by Emperor Geldoblame to the acting ambassador of Diadem as a form of humiliation, which he chose because, due to Lyude's connections to the Alfard Honor, he could not execute him despite personally desiring that punishment. This also worsened his already-tenuous relationship with his family, in particular his siblings, which was already at a low point due to the events of his birth. As a result of the massacre, the town was largely a desolate town, with the survivors living in constant fear. Lyude himself was also disgusted with his cowardly reaction to Geldoblame's wrath to him.
A year later, Lyude recounted the events of the massacre when he, Kalas, Xelha, Gibari, and Mizuti arrived at Azha in an attempt to stop Geldoblame from unsealing the final End Magnus that was located in the Lava Caves. He also learned that Savyna had been involved in the massacre and was disgusted with this revelation before Xelha requested that they put it behind them for the time being due to having more important matters to attend to. Ironically, Geldoblame himself would end up meeting a similar fate to the deceased victims of the massacre by being shot into the lava flows after, upon being transformed into a grotesque monster via the unsealed Malpercio's dark energies and losing control of his body due to the nature of Malpercio's creation, he ended up betrayed by Fadroh and Melodia, the latter of whom was his most trusted servant. Lyude would later recall upon visiting the throne room of the Imperial Fortress the day that Geldoblame gave the order to commence Operation Sweep, and somberly mentioned that after that day, he stopped being a coward. The heroes later revisited the Lava Caves and attempted to quell the various souls of the victims of the massacre while infiltrating Cor Hydra.