Defense of Mon Calamari (Yuuzhan Vong War)

Leading up to the confrontation, the Yuuzhan Vong were experiencing setbacks, losing ground to the Galactic Alliance at an increasing rate, and the World Brain situated on Yuuzhan'tar was encountering difficulties with its terraforming endeavors. Despite suffering the loss of one-third of the entire Warrior caste throughout the invasion and facing overextended resources, Supreme Overlord Shimrra commanded a large-scale offensive against Mon Calamari, which served as the Galactic Alliance's temporary capital. The Galactic Alliance strategically exploited this situation by dividing their forces, dispatching half to Yuuzhan'tar while the remaining forces were tasked with defending Mon Calamari.

During the course of the battle, Lieutenant Colonel Jaina Solo, alongside numerous pilots, crew members, and gunners, engaged in combat within the space surrounding Mon Calamari. The Yuuzhan Vong fleet was arranged in a formation resembling a yammosk. Each of its tendrils contained hundreds of Yuuzhan Vong warships. The actual yammosk vessels occupied the center of this formation, shielded by a multitude of warships, battleships, and coralskippers. To disrupt their organizational efforts, the Galactic Alliance dispatched a team consisting of Kyp Durron, Han, and Leia Organa Solo with the objective of eliminating a yammosk located on the nearby planet of Caluula. The yammosk served as a coordination tool for the extragalactic aliens to manage their forces during combat. With the destruction of a yammosk, the Yuuzhan Vong forces would become disorganized.

Subsequently, it was revealed that the biological weapon known as Alpha Red was responsible for the yammosk's demise, and it also inflicted significant damage to Caluula's biosphere. In 28 ABY, Vergere had previously sabotaged and destroyed Alpha Red, although certain factions within the New Republic Intelligence Service had revived the project and deployed it on Caluula. While Alpha Red effectively eradicated all Yuuzhan Vong lifeforms in its path, its efficiency was not as anticipated, and it also posed a contamination risk to non-Yuuzhan Vong life forms. To compound matters, a Yuuzhan Vong vessel infected with the disease had escaped Caluula and was en route to Yuuzhan'tar.

Despite the loss of the yammosk at Caluula, the Yuuzhan Vong persisted in their assault. In reality, they had never intended to utilize Caluula or Toong'L as fallback positions. Admiral Traest Kre'fey was on the verge of issuing a retreat order when the Yuuzhan Vong fleet received information that Zonama Sekot had entered the Yuuzhan'tar system. Recognizing the paramount importance of Yuuzhan'tar, Warmaster Nas Choka commanded the fleet to withdraw, effectively bringing the battle of Mon Calamari to a conclusion.