The Nathema Zealots, established by Emperor Valkorion of the Eternal Empire, were a collective of exceptionally powerful Force-sensitive individuals. These Zealots stood apart, uniquely capable of enduring the Void's horrors through rigorous daily rituals and intensive meditation.
This form of mental training sharpened their focus and enhanced their power, but simultaneously diminished their autonomy, enabling Valkorion to forge an entirely obedient army of potent Force users. During this conditioning process, an unforeseen consequence emerged: their adaptation to the Void led to a dependence on it for survival. Leaving Nathema would plunge a Zealot into a non-responsive, catatonic state.
Seeing this as a less-than-successful experiment, Emperor Valkorion repurposed the Zealots, assigning them to serve as an elite guard, specifically as wardens for the prisoners confined within Nathema's Sanitarium. Among these prisoners was the Emperor's own daughter, Vaylin, who was subjected to a ritual intended to shatter her spirit and control her mind.
When Senya Tirall infiltrated the facility to rescue Vaylin, six Nathema Zealots, clad in their distinctive black armor and robes, confronted her on a bridge, attempting to thwart her escape. Senya, armed with her lightsaber pike, engaged and defeated all six Zealots, even turning their own yellow-bladed lightsabers against them. However, Vaylin's refusal to leave with her mother prompted the arrival of more Zealots, accompanied by Valkorion, from the Sanitarium to reclaim his daughter.
Following Vaylin's return to Zakuul, the Sanitarium was abandoned, yet the Nathema Zealots remained. Years later, Vaylin revisited the Sanitarium to undergo a perilous procedure aimed at reversing her conditioning. The Zealots aided Jarak and the Keepers in their preparations for the treatment. Shortly after Vaylin's arrival, the Outlander and Lana Beniko invaded the Sanitarium, battling the Zealots who were not involved with Vaylin's treatment. As Vaylin's true power manifested, the Zealots fled the exploding machinery and the deadly cloud she unleashed. Now fully in control, Vaylin returned to her fleet and commanded the Sanitarium's destruction.
After the Eternal Empire's collapse, the Zealots who survived sensed Valkorion's demise through the Force, but they were in denial. The zealots splintered into various tribes, engaging in raids and mutual destruction. To survive, the Zealots sustained themselves by consuming the nascent life flourishing on the planet.