The conflict known as the Battle of Quell unfolded in 21 BBY—equivalent to 2 BFE—during the era of the Clone Wars. This engagement commenced in orbit around, and subsequently within the upper atmosphere of, the planet Quell. The fleet of the Galactic Republic, led by Jedi General Aayla Secura, found itself under assault from a squadron of Munificent-class star frigates belonging to the Confederacy of Independent Systems, under the command of the T-series military strategic analysis and tactics droid designated TF-1726. As her forces sustained significant damage from the Separatist squadron, Secura requested assistance from fellow Jedi General Anakin Skywalker and his Padawan, Ahsoka Tano. They journeyed across the galaxy aboard Skywalker's flagship, the Venator-class Star Destroyer Resolute, arriving just in time to initiate a rescue operation.
During the course of the battle, both of Secura's supporting Star Destroyers were obliterated by the Separatist capital ships. Her flagship, the Venator-class Star Destroyer Liberty, was subjected to a boarding action by numerous B2-RP super battle droids, coupled with relentless heavy turbolaser fire from the Separatist frigates. Upon Skywalker's arrival, he proceeded to board the Liberty while a Consular-class cruiser docked in the lower hangar with the aim of extracting Secura and the remaining personnel from the doomed vessel. However, during their escape, Skywalker suffered severe injuries when he used the Force to contain an explosion, allowing Secura, his Padawan, the Clone Captain Rex, and Clone Marshal Commander Bly to board the rescue frigate. As they departed Secura's failing flagship, the Republic frigate sustained damage from Separatist cannon fire, causing it to enter hyperspace on an unpredictable course. This prompted Admiral Wullf Yularen to calculate the ship's trajectory after the battle's conclusion in order to locate them.
By the time the fighting ceased, although Secura had been rescued, the Republic had endured substantial losses among her 327th Star Corps of clone troopers and a significant portion of the clone crews serving aboard the three Republic Star Destroyers, who were unable to evacuate the destroyed vessels before they crashed onto the planet's surface. While the Separatist victory was decisive, it also highlighted the uncertainty surrounding the Republic's eventual triumph in the war.
Throughout the duration of the Clone Wars, a widespread conflict between the Galactic Republic and the Confederacy of Independent Systems, the Separatist alliance frequently leveraged the numerical advantage of its naval forces in engagements against the Republic. This tactic was employed by the Confederacy during battles fought within the Outer Rim Territories, a region of the galaxy where separatist sentiment was prevalent, notably during the conflict that occurred at the planet Quell.
In the year 21 BBY, Aayla Secura, a Twi'lek Jedi General, along with her task force consisting of three Venator-class Star Destroyers with the Star Destroyer Liberty as flagship, found themselves in a battle against a squadron of five Munificent-class star frigates. These frigates were under the command of TF-1726, a T-series military strategic analysis and tactics droid, who directed the battle from his command ship in orbit around Quell, situated in the Outer Rim. Throughout the engagement, both the Republic and Separatist capital ships launched numerous starfighters against each other. Secura deployed several groups of V-19 Torrent starfighters, while the tactical droid dispatched Vulture-class droid starfighters.
After the Separatist squadron lost one of its frigates, the remaining capital ships intensified their turbolaser fire on the Republic Star Destroyers, eventually forcing them into the planet's upper atmosphere. The other two Venators were destroyed, crashing onto Quell's surface in flames. With the destruction of her supporting Star Destroyers, the Liberty was left outnumbered as it struggled to maintain altitude in the atmosphere. Despite the Liberty's attempts to return turbolaser fire, the Star Destroyer continued to sustain heavy Separatist fire and ultimately lost power to its deflector shields after being struck.
Following the deactivation of the Republic flagship's shields, TF-1726 gave the order to deploy dozens of jetpack-equipped B2-RP super battle droids from his command ship to board the heavily damaged Star Destroyer through breaches in its hull. To reinforce the rocket droids, B1-series battle droids were also sent aboard the Liberty, prompting Secura to instruct her Clone Commander, CC-5052, known as "Bly," to repel the invaders. In compliance with her orders, Bly led several groups of clone troopers from the 327th Star Corps to engage the boarding battle droids.
As her forces suffered significant casualties, fellow Jedi General Anakin Skywalker, aboard his flagship, the Venator-class Star Destroyer Resolute, received news of Secura's plight and traveled across the galaxy to assist her in the battle. Upon the Resolute's entry into the atmosphere after arriving in the Quell system, Skywalker, accompanied by his Padawan, Jedi Commander Ahsoka Tano, Clone Captain CT-7567, known as "Rex," and clone troopers from the 501st Legion, departed aboard several Low Altitude Assault Transport/infantry gunships. Their mission was to board the heavily damaged Liberty and rescue its crew before its destruction, while Admiral Wullf Yularen remained on the Resolute. Skywalker also arranged for a retrofitted Consular-class cruiser to dock with Secura's flagship for evacuation purposes.
During their descent to Secura's Star Destroyer, Skywalker and his gunship force were intercepted by several rocket droids that had been boarding the Liberty. As the droids fired their blasters at the gunships, the Republic craft retaliated with laser cannon fire and missiles. One of the rocket droids attached itself to the craft carrying Skywalker, his Padawan, and Rex, tearing open the cockpit canopy in an attempt to kill the clone trooper pilot. The pilot evacuated into the troop compartment while Skywalker jumped onto one of the droids and made his way onto the Liberty. The gunship, now out of control, crashed into the Star Destroyer's hull. After the crash, Tano, Rex, and several clone troopers exited the gunship and engaged the invading rocket droids and B1 battle droids, eventually meeting up with Secura and Bly in a hallway after destroying several of the droids.
While aboard the Liberty, TF-1726, growing impatient with the prolonged fighting, ordered his droid crew to open fire on the Star Destroyer, disregarding the fact that hundreds of their own droids were still aboard and would be destroyed. As Skywalker and Secura continued to fight off the battle droids, they eventually met up with Tano and Rex and continued to advance through the Star Destroyer's corridors, destroying Separatist droids along the way. In response to an inquiry about his rescue plan, Skywalker explained that a Republic frigate was docking in the lower hangar for evacuation. As the frigate docked, the Republic survivors extended the gangway and boarded, but were temporarily halted by a wall of flames caused by intense Separatist fire, which consumed all clone troopers and battle droids in its path. Upon seeing the flames, Skywalker used the Force to push his allies into the frigate and hold the flames back.
Skywalker was rescued, and the cruiser departed the doomed Republic vessel just as it was being destroyed. Due to Skywalker's wounds, Secura sought to dock with the Resolute, which was engaging Separatist forces. Wullf Yularen warned about docking in the middle of the battle, but reluctantly allowed Secura and the cruiser to dock. However, during the docking procedure, the cruiser was attacked by vulture droids, which accidentally activated the ship's hyperdrive, forcing the cruiser into evasive action to avoid a catastrophic collision with the Resolute as it jumped into hyperspace.
Yularen ordered the last known trajectory of the cruiser be plotted so the missing ship could be located after the battle. Ultimately, the battle was a Separatist victory.
The out-of-control ship nearly collided with a star in hyperspace, but after it was forced out, the ship crashed on the planet Maridun. The stranded Jedi and clones found medical assistance for Skywalker at a village of Lurmen colonists. However, not long after their arrival, Separatist forces led by General Lok Durd arrived at Maridun, plotting to destroy the village as part of a test for Durd's experimental weapon, the Defoliator. The Republic group, including a mostly-recovered Skywalker, successfully defended the village from Durd's forces, before capturing him just before the Resolute arrived at Maridun in search of them.
The initial depiction of the Battle of Quell occurred in the episode "Jedi Crash," which was the thirteenth episode of the first season of the animated television series Star Wars: The Clone Wars. It was broadcast on January 16, 2009. The battle's identification was provided in the accompanying episode guide on StarWars.com. Within the Star Wars Legends continuity, the battle was first identified as the Sky Battle of Quell in the entry dedicated to Ahsoka Tano on StarWars.com.
In the original script for "Jedi Crash," the Battle of Quell was initially conceived as a space battle. However, during the episode's pre-production phase, it was relocated to Quell's upper atmosphere to enhance the dramatic impact. These alterations to the battle sequence resulted in continuity inconsistencies regarding the operational capabilities of hyperdrives, which canon had previously established as having limitations when operating near planets.