Tranquility

Being a Venator-class Star Destroyer, the Tranquility featured a pair of command bridges, eight engine units, and escape pods. This Star Destroyer included a hangar bay that held multiple Low Altitude Assault Transport/infantry gunships, along with a ventral docking bay large enough for a single retrofitted Consular-class cruiser. The Tranquility was armed with eight DBY-827 heavy turbolaser turrets on both the port and starboard sides, controllable from the bridge, and two medium dual turbolaser cannons per side as well. The Open Circle Fleet's emblem was displayed on the hull of the Tranquility, on both the port and starboard sides.

The Venator possessed a highly secured detention level that contained multiple cells, each protected by a ray shield controlled by panels located beside them. These shields could also withstand multiple blaster shots from a DC-15A blaster carbine and lightsaber strikes. The detention level's entrance, accessible via several turbolifts, was a control center that displayed the ship's operational status, including its turbolifts, doors, propulsion, and communications systems. The Tranquility also had a spacious engine room accessible through a door or the ship's ventilation system, featuring three vertical reactors and walkways at varying heights to facilitate movement for the Tranquility's crew.

During the Clone Wars in 22 BBY between the Galactic Republic and the Confederacy of Independent Systems, Senator Padmé Amidala undertook a mission to the planet Rodia to reaffirm its allegiance to the Republic. Upon her arrival, battle droids under the command of Trade Federation Viceroy Nute Gunray captured Amidala, prompting her protocol droid, C-3PO, to use a military code to alert Republic clone troopers about the situation. Consequently, the Republic dispatched the Tranquility, led by Jedi Master Luminara Unduli and her Padawan Ahsoka Tano, along with the clone troopers of the 41st Elite Corps' Green Company, to Rodia to rescue the Senator and capture the Viceroy. Gunray was intended to be transported to the Republic capital, the planet Coruscant, to face trial for his offenses.

Subsequently, in 21 BBY, Gunray was placed on a modified Consular-class cruiser, accompanied by both Jedi and clone troopers, for transport to the Star Destroyer. Unduli contacted the Tranquility while en route, requesting permission to dock with Gunray in custody. Senate Commando Captain Faro Argyus granted the cruiser permission to dock, and it proceeded to its designated position in the Venator's ventral docking bay. Upon their arrival aboard the Tranquility, a squad of Senate Commandos, along with Clone Commander CC-1004, known as "Gree," escorted the Viceroy to a cell in the detention center.

While Gunray was detained within the ray-shielded cell, the Jedi interrogated him, hoping to uncover Confederacy secrets. However, during the interrogation, the Tranquility was attacked by a group of three Droch-class broading ships escorted by a squadron of Vulture-class droid starfighters. Despite efforts to shoot them down, the boarding ships penetrated the Star Destroyer's hull and deployed a number of B2-series super battle droids into the Tranquility's hangar bay against the clone troopers of Green Company, leading to a firefight aboard the Tranquility as the clones attempted to repel the battle droids.

Despite their best efforts, the super battle droids overwhelmed the troopers in the hangar and advanced further. The Green Leader of the Republic company reported their movements toward the detention level to the Clone Commander, prompting Unduli and Gree to assist the clone troopers. As the droids continued their advance into the Tranquility, diverting clones away from the hangar, Sith assassin and Dark Acolyte Asajj Ventress, dispatched by Separatist Head of State Count Dooku to either retrieve or eliminate the Viceroy, secretly entered the Tranquility's engine room through the ship's ventilation system while the droids engaged the clones.

As the clones fought the battle droids within the Tranquility, Ventress infiltrated the Star Destroyer's engine room and planted several thermal detonators throughout the area, avoiding detection by the WED-15 Treadwell droid, 327-T. Subsequently, the Sith assassin returned to the ventilation system and made her way to the detention level, entering through a hole she created in the ceiling using her lightsabers, where she engaged Tano and Senate Commandos. Unduli, believing the initial attack had been successfully repelled, returned to the detention level after sensing Tano's peril through the Force.

During the battle between Tano and Ventress, the Sith assassin freed the Viceroy from his cell, resulting in Tano being trapped within the cell as she attempted to attack Ventress. Upon Tano's entrapment, Unduli arrived and freed the Padawan, and the two briefly clashed blades with the Dark Acolyte, forcing Ventress to momentarily surrender as her explosives detonated throughout the engine room, giving Ventress an opportunity to escape. The resulting explosion engulfed the engine room in flames and crippled the Tranquility, disabling its communications and propulsion systems, as well as the Star Destroyer's turbolifts and doors.

After Ventress fled from the two Jedi, Master Unduli went to search for her, while Tano remained in the detention level. Tracking her to the ship's engine room, Unduli engaged the assassin upon entering, resulting in her vision being impaired when Ventress struck a pipe, causing steam to enter the Jedi Master's left eye. After a prolonged dueling in the engine room, Ventress knocked Unduli down and trapped her under metal pipes running along the ceiling of the Tranquility's engine room. However, before the assassin could kill the trapped Jedi Master, Tano entered the room and freed Unduli, resulting in a duel between the two Jedi and the Sith assassin throughout the engine room.

Argyus and Gree fought, and Gree seemed to gain the advantage after delivering a serious blow to Argyus, only for Gunray to knock out the clone from behind. Argyus then signaled to Ventress, who quickly escaped from the Jedi. Argyus and Gunray fled the Tranquility aboard the cruiser that had originally brought the Separatist leader from Rodia, and Ventress soon joined them, jettisoning from the Tranquility via escape pod. Argyus boasted about the mission's success but was then killed by Ventress.

Unduli and Tano, aboard the Tranquility, reported the situation to Yoda and Anakin Skywalker. Despite losing Gunray, they believed they could track him since he had commandeered a Republic ship—information that was passed onto the nearby Jedi Master Kit Fisto. Fisto later tracked the ship to Vassek 3, where he unknowingly led his team into a trap set by Dooku, venturing into the lair of General Grievous.

The Tranquility made its debut in "Bombad Jedi," the eighth episode of Star Wars: The Clone Wars' first season, which premiered on November 21, 2008. The ship was subsequently identified in the first season's ninth episode, "Cloak of Darkness," which was originally broadcast on December 5 of the same year.

The catwalks and cylinder clusters in the engine room are an architectural homage to the gravity control room aboard the Super Dimensional Fortress (SDF-1) from the Macross anime.