The events known as the Battle of Yinchorr transpired on the planet Yinchorr during the year 33 BBY, coinciding with the period of conflict called the Yinchorri Uprising.
After successfully navigating past the Yinchorri forces in space, a Consular-class space cruiser carrying Jedi Masters Mace Windu, Qui-Gon Jinn, Saesee Tiin, and Padawan Obi-Wan Kenobi touched down on Yinchorr, the Yinchorri's harsh desert home world. Their mission was to locate a rumored Yinchorri high command. Upon landing, the Jedi secured their vessel and then proceeded towards a mountain, establishing a temporary operational base. Qui-Gon, accompanied by his Padawan, embarked on a reconnaissance mission to locate the Yinchorri command. Instead of the command, they discovered the Yinchorri were amassing their military forces. Barely managing to escape the Yinchorri, the two Jedi returned to the temporary base, relaying their findings to Mace Windu and Saesee Tiin.
While they were reporting, their nearby transport exploded. Qui-Gon pointed out that the Yinchorri had found their ship. Mace responded that ships were replaceable. Tiin then inquired about Qui-Gon's observations. Qui-Gon stated that he didn't find any sign of a military command post, but instead a military staging area for an invasion outside a city's walls. Mace Windu then asked Qui-Gon to describe the layout of the staging area, and informed the group that Master Adi Gallia and others would arrive soon, signaling the time to act against the Yinchorri was approaching.
Before long, the four Jedi found themselves encircled by a Yinchorri army, against which they fought with great courage. However, the Yinchorri then deployed flutter-packs and tanks. Fortunately, their allies arrived aboard a Consular-class space cruiser and began engaging the Yinchorri forces. This group of reinforcements included Micah Giiett, Lilit Twoseas, Plo Koon, K'Kruhk and Eeth Koth, while Adi Gallia, Tsui Choi and Theen Fida stayed behind at the cruiser to guard it and monitor their prisoner, Vilmarh Grahrk.
These five Jedi formed a wedge formation, breaking through the Yinchorri ranks. This action diverted the attacks away from Mace Windu's team, which in turn allowed Windu's team to assist them, thus creating a two-pronged attack against the Yinchorri. Mace Windu then instructed his group to rendezvous with the other five Jedi. During their advance, Saesee Tiin encountered an enemy tank, eliminating the driver with his lightsaber before safely jumping away. Simultaneously, the cruiser was attacked by a larger number of Yinchorri forces, including a tank.
Back at the primary battle area, Windu and his Jedi attempted to bring the conflict to a close and return to the cruiser as quickly as possible. During the fighting, K'Kruhk was targeted by a Yinchorri warrior, prompting his Master Lilit to intervene. Sadly, she was seriously injured in the process. Fortunately, her fellow Jedi used the Force to repel the attacking Yinchorri. Micah recognized the urgency of getting Lilit back to the ship for medical attention. Consequently, while Mace Windu, Saesee Tiin, Eeth Koth, and K'Kruhk hurried back to the ship with Lilit, Micah, Qui-Gon, Plo Koon, and Obi-Wan provided covering fire.
However, upon reaching the cruiser, they discovered that another battle had occurred. All the Yinchorri attackers had been killed, but so had Padawan Theen Fida. Mace Windu then urged his fellow Jedi to set aside their grief, emphasizing the need to complete their mission of locating the Yinchorri high command and to place Twoseas and Fida on the ship. Lilit would later succumb to her injuries. He also instructed Saesee Tiin to prepare the cruiser for departure and attempt to transmit a message to Master Yoda at the Jedi Temple on Coruscant. After boarding the ship, they discovered that Grahrk had escaped and was at the controls, trying to contact someone, unaware that this individual was Darth Sidious.
They then managed to transmit a message to the Jedi Temple, reporting their findings to the Jedi Council. Back on Coruscant, Yaddle revealed that she had consulted the holocron of Master Tharence Wo and learned of a fourth moon in the Yinchorri system. This moon was a barren, rocky world known as Uhanayih, which meant "Within World" in the Yinchorri language. Mace Windu then sent another transmission to the Jedi Temple, confirming that the hidden command center was located on a lifeless rocky planetoid near the system's star, and instructed his fellow Jedi to inform Supreme Chancellor Finis Valorum of these discoveries.
Returning to the battlefield, Micah Giett was shot in the back by a Yinchorri warrior. As he lay dying, Micah instructed Plo Koon to move him to one of the destroyed enemy tanks, positioning him with his back against it. Before passing away, he urged his comrades not to give in to emotions, including revenge, and that the Yinchorri had to be stopped. He also cautioned them to use deadly force only to preserve lives.
As soon as his comrades had left, Micah was surrounded by a group of Yinchorri. He beckoned them closer, pretending to share "Jedi secrets." When they approached, he declared that the Jedi were not afraid to die for a worthy cause, then activated his lightsaber, plunging it into the tank's fuel cell. The resulting explosion killed Giett and likely many of the Yinchorri. Giett's death was transmitted through the Force, felt by his Jedi companions across the galaxy. Even Darth Sidious himself sensed it in the Force. The Dark Lord then commanded his apprentice Darth Maul to retrieve Vilmarh Grahrk.
In the meantime, the surviving Jedi departed on their transport, heading to Uhanayih to eliminate the Yinchorri threat, just as Finis Valorum dispatched four Republic Navy attack groups to the Yinchorri system.