During the time of the Great Jedi Purge, the crew of the Mantis embarked on a quest to Nur, a moon covered in water, with the goal of recovering a Jedi holocron. This holocron was located within Fortress Inquisitorius, which served as the base of operations for the Inquisitorius under the rule of the Galactic Empire.
The _Stinger Mantis'_s crew had traveled the galaxy following the path of Jedi Master Eno Cordova to locate a Jedi holocron, hoping to rebuild the Jedi Order. After Cal Kestis opened the Zeffo vault on Bogano and obtained the holocron, the Second Sister, also known as Trilla Suduri, ambushed him and engaged in a lightsaber duel. Kestis was weakened upon touching the Second Sister's lightsaber, experiencing her capture through psychometry, which allowed the Second Sister to escape with the holocron. Subsequently, Cere Junda, the Second Sister's former master, realized that Suduri would take the holocron to the Fortress Inquisitorius on Nur, the birthplace of all Inquisitors.
Thanks to a ritual performed by Nightsister Merrin, the Stinger Mantis successfully approached the Fortress undetected. Kestis and Junda infiltrated the Fortress by jumping into the ocean and entering through an airlock. Kestis and Junda fought their way through the Fortress separately, with Junda eventually holding back Imperial reinforcements. Kestis continued towards the center of the Fortress, where the holocron and the Second Sister were located. A fierce duel ensued between Kestis and the Second Sister, which Kestis ultimately won.
Junda arrived and tried to persuade her former apprentice to reject the dark side of the Force, but they were suddenly confronted by Darth Vader, who immediately killed Suduri for failing him. Kestis and Junda attempted to fight Vader, but they were easily overpowered by the Sith Lord. Vader threw Junda into a pit. When Kestis attempted to attack Vader, he was quickly restrained telekinetically. Kestis attempted to throw a generator at Vader, but Vader deflected it and threw Kestis out of the room, forcing the Jedi to flee. After escaping from the Sith Lord, Kestis thought he was safe, but Vader cut him off. Kestis narrowly survived thanks to Junda's intervention. Junda almost succumbed to the dark side to slow Vader down, but Kestis convinced her otherwise. Instead, Kestis flooded the corridor, forcing Vader to focus on containing the water, which allowed the Jedi to escape.
The holocron's acquisition would have allowed Kestis and Junda to find Force-sensitive children throughout the galaxy. However, Kestis chose to let the Force decide their destinies and destroyed the holocron. Following this decision, the crew of the Stinger Mantis departed in search of new adventures.