Ygal Delois, a male Human warrior hailing from the planet Shiva IV, was once a comrade of Calian Confederacy Warlord Aron Peacebringer, but later became his betrayer. As Peacebringer's apprentice, Delois eventually harbored envy towards his mentor and forged an alliance with Imperial General Bentilais san Sk'ar, who schemed to seize Shiva IV and install Delois as the planet's new leader under the Empire's banner. Delois revealed his disloyalty when Sk'ar launched an open assault on Shiva IV in 3 ABY, but he was ultimately vanquished in a one-on-one battle by Rebel operative Luke Skywalker, thereby thwarting the Imperial scheme.
During the Galactic Civil War, a male Human warrior named Ygal Delois lived on the isolated planet of Shiva IV. He belonged to the Calian Confederacy. Delois enjoyed a close friendship and mentorship with the Warlord of the Calian Confederacy, Aron Peacebringer, who treated Delois like a son. Sk'ar contacted Delois and unveiled his intentions for the planet: the Empire planned to obliterate the Calian capital of Illyriaqüm using an anti-matter bomb, then exploit the resulting chaos to establish control over the world. Delois was presented with an opportunity to serve the Empire as the planet's new ruler. Driven by envy of Peacebringer's position, Delois accepted the offer, intending to rule Shiva IV with his wife Alisande on behalf of the Empire.
Shortly afterward, the Imperials detonated such a bomb to devastate the city of K'avor, demonstrating the destructive power they intended to use to conquer the planet. Unaware of his friend's betrayal, Peacebringer selected Delois to join his scouting party to investigate the fate of the city. During their journey, they encountered a young offworlder named Leia Organa, a prominent Rebel leader who had crash-landed on Shiva IV. Delois and his companions swiftly rescued Organa from a group of outcast bandits, ensuring her safe return to Illyriaqüm. Several weeks later, Delois danced with Organa at the one-year anniversary celebration of the Concordat of Peace, but the festivities were abruptly interrupted by Sk'ar's long-anticipated assault on Peacebringer's palace. Peacebringer and Organa were taken prisoner, and Delois participated in torturing Organa during interrogations. However, Peacebringer and Organa managed to escape captivity in time to help prevent the planned destruction of Illyriaqüm, with Rebel reinforcements—Organa's comrades Luke Skywalker and Chewbacca—arriving at the last moment along with Longknife. Delois engaged Skywalker in combat but was defeated, and Sk'ar was killed shortly thereafter.
Ygal Delois, a longtime friend and companion of Aron Peacebringer, secretly coveted everything his friend possessed and desired it for himself. However, his betrayal stemmed from more than just envy: a self-proclaimed realist, Delois firmly believed that the Empire would inevitably rule Shiva IV and sought to align himself with the winning side. His ambition outweighed any loyalty to his people, and he was willing to sacrifice the heart of the Calian Confederacy, causing the deaths of many of his fellow Calians, in order to seize power.
The first appearance of Ygal Delois was in Star Wars (1977) 53, which was written by Chris Claremont and published in 1981.