The Force walk was a venerable Dark Side method employed by the Sith of old, enabling them to tether unsettled Force spirits to the corporeal realm, thereby harnessing their latent abilities.
A Sith practitioner, possessing immense willpower, had the ability to shackle the wandering spirits of deceased Sith to their own being. Upon successful binding, the practitioner gained access to the spirit's inherent power, channeling it into a potent surge of Force energy. Compelling a spirit against its will yielded a greater power surge, whereas cooperation diminished the effect. Those proficient in this technique experienced rapid ascensions, followed by inexplicable declines, shrouded in mystery. Only Darth Nox and Lord Ergast, whose demise also remained enigmatic, managed to bind multiple spirits. It seemed that an excessive number of bound spirits could rapidly overwhelm the host, inducing both physical and spiritual ailments, culminating in uncontrolled and violent manifestations of Force power. Nevertheless, a rumored remedy existed on both Belsavis and Voss, which, if discovered, could negate the adverse effects, allowing the practitioner to bind an unlimited number of spirits.
Three centuries following the passing of Tulak Hord, the Sith Lord Ergast endeavored to replicate the dark ritual employed by the Dark Lord to consume the essences of his adversaries at Yn and Chabosh. His efforts, however, led to the discovery of a new ritual, which he subsequently named Force-walking.