Nym, a pirate, utilized Nym's Base as his primary headquarters and sanctuary along with his Lok Revenants. This period extended from before the Invasion of Naboo up to the Galactic Civil War. Throughout the Occupation of Karthakk, the base was the subject of several reconstructions due to conflicts between Nym and the Trade Federation. By the time the Galactic Civil War began, the area around the base had developed into a city known as Nym's Stronghold, and the base itself was most commonly referred to as Nym's Keep.
The base was situated within the Nym Protectorate, a relatively barren area on the surface of Lok. It was built inside a crater that was near the Grendin River.
Although seemingly vulnerable, Nym's base possessed numerous hidden defensive measures. A hangar was integrated into the base, facilitating the launch of the Havoc and other Revenant starfighters. Constructed within a crater, the base's main defenses consisted of two turrets positioned at the entrance, with additional turrets dispersed throughout the interior. Inside, three large cargo freighters and two smaller freighters were stationed. The Inferno Turret served as the primary defensive weapon. During the Trade Federation's assault, it successfully prevented a C-9979 landing craft from landing within the base. This turret featured a rotating five-barrel cannon, along with dual laser cannons positioned on the top and side.
The Lok Revenants used the base as their operational center, frequently attacking passing Trade Federation supply ships in orbit, forcing them down and salvaging their cargo. The exact duration of Nym's use of the base remains unknown, but by 32 BBY it was already a well-established location.
The situation deteriorated for Nym when he and his Revenants attacked a Trade Federation Superfreighter that was transporting prototype Vulture droid starfighters. While the Federation had previously overlooked the Revenants' attacks, this particular cargo was deemed too important. Consequently, they launched a full-scale invasion of Lok, compelling Nym and his allies to retreat under heavy fire. Nym rescued his aide, Jinkins, from near-certain death during the attack, and Jinkins accompanied the evacuation transports as they departed Lok.
After Nym was driven off the planet, the Federation seized control of the base and implemented significant modifications. The open crater was sealed with a massive dome, and the interior was repurposed into a droid foundry and hangar.
The hangars were repurposed as fueling stations for Federation freighters. In 22 BBY, the returning Revenants destroyed these stations during a battle using an orbital cannon constructed on one of Lok's moons. Following the death of Lieutenant Bella, Nym regained control of the base after his assault on the complex.
During the Galactic Civil War, Nym rose to become the leader of Lok and continued to operate from the base. By this time, the base had undergone another substantial transformation. Nym's Stronghold, a city, had grown up around the fortress. By the time of the Battle of Yavin, it had become the largest city on Lok and housed the planet's only spaceport. The base was converted into a palace, where Nym, Kole, Jinkins, and Vana Sage were frequently present. They were known to hire various spacers for different missions.