Skal'nas, a male Rakata Predor hailing from the Infinite Empire, was known for his ruthlessness, even amongst his own kind. Highly skilled in both combat and deception, he rose through the ranks from humble origins, marked by a volatile temper. When Trill, Skal'nas's Force Hound, detected a Force-rich planet situated deep within the Deep Core but couldn't pinpoint its location, Skal'nas requested the assistance of Predor Tul'kar and his Force Hound, Xesh. Upon Xesh's claim of being able to find the world, Skal'nas adhered to protocol, granting Tul'kar the lead in the invasion, while stipulating that they would share the spoils. The planned invasion, however, failed when Tul'kar's vessel crashed on Tython, and Tul'kar was subsequently killed by Xesh. Unaware of these events, Skal'nas presumed that Tul'kar had disabled his ship's communication systems to claim the planet entirely for himself. Incensed, he dispatched Trill to locate Tython, along with Xesh and Tul'kar, with orders to bring them back, dead or alive.
Skal'nas, like others of his species, was sensitive to the Force, having been born in Infinite Space. He became notorious for his ruthlessness, even by Rakata standards, and his proficiency in combat and treachery was matched only by his quick temper.
Skal'nas joined the ranks of the Infinite Empire, climbing the ladder through relentless fighting and brutality, eventually achieving the rank of Predor. He later became the superior of Predor Tul'kar and Sub-Predor Ceh'let, a position that Tul'kar resented. At one point, Xesh, Tul'kar's Force Hound, engaged in a duel with the Force Hound Trill, but Xesh spared her life, suggesting that Tul'kar present Trill to Skal'nas as a gift, an offer which Skal'nas gladly accepted.
On one occasion, Skal'nas tasked Tul'kar with capturing Tatooine, a world rich in the Force. During the culling process, the planet's massive cities were devastated, ultimately transforming Tatooine into a desert wasteland. While transporting the Force-sensitives, Skal'nas dispatched Ore'mun to Tatooine to relieve Tul'kar of his duties and oversee the culling, instructing Tul'kar to return to Rakata Space. However, Tul'kar murdered and devoured Skal'nas' messenger. Soon after, Tul'kar, accompanied by Xesh, returned to Skal'nas' stronghold on Byss to ascertain Skal'nas' intentions. Skal'nas informed Tul'kar that Trill had detected a Force-rich world within the Deep Core, but was unable to locate it precisely. When Xesh claimed to be able to pinpoint the planet, Skal'nas, following protocol, authorized Tul'kar to lead the invasion, but stipulated that the spoils would be shared. Unbeknownst to Tul'kar, Skal'nas had secretly gained influence over Xesh, turning him into his personal spy.
During the invasion, Xesh murdered Tul'kar, and Tul'kar's ship crashed on Tython. Not knowing the fate of the Rakatan fleet, Skal'nas flew into a rage, suspecting that Tul'kar had disabled his ship's reporting device to claim the planet for himself. Consequently, he dispatched Trill to hunt down Tython, as well as Xesh and Tul'kar, with orders to bring them back, dead or alive.
Later, Skal'nas continued the planned invasion of the Tython system, with Sub-Predor Ceh'let assisting him. During the invasion, Skal'nas and his fleet encountered the Je'daii, who fiercely defended their home. When Ceh'let's ship came under heavy fire, Skal'nas ordered her to retreat. She complied, but not before openly defying him. Skal'nas retreated to Ska Gora, where Ceh'let later joined him. Skal'nas revealed to Ceh'let that the Rakata were beginning to lose their Force-sensitivity and that they would need to utilize the Infinity Gate on Tython. He also falsely claimed that they would rule Tython together once the Je'daii were defeated. Once Ceh'let lowered her guard, Skal'nas killed her with Force lightning as punishment for her defiance.
Subsequently, on Tython, Skal'nas faced both Xesh and his brother in a duel, only to be fatally wounded across the chest and fall into a pool of acid, meeting his demise.