Giles Durane, known by the moniker "Weapons Master," was a seasoned Human male veteran and a comrade of Bail Prestor Organa, with whom he fought alongside during the Clone Wars. A plague devastated Durane's homeworld, resulting in the death of his family. Impoverished and disillusioned, Durane transitioned into a mercenary. As time passed, Durane consented to instruct Organa's daughter, Leia, in the art of wielding weapons.
During the era of the Clone Wars, Giles Durane possessed the qualities of a kindhearted idealist. He served alongside Bail Organa, who, on numerous occasions, saved Durane's life. Early in the war, while accompanying the senator on a mission to Virgillia 7, Durane collaborated with Jedi Master Ashka Boda to successfully extract Jedi Padawan Halagad Ventor and his master, Everen Ettene, from the ground conflict. Although Ettene did not survive the mission, Durane and Boda managed to rescue Jedi Ventor. Durane even provided training to Organa's bodyguard, Sateen Vestswe. As the galactic conflict drew to a close, Durane found himself in such dire financial straits that he lacked the resources to evacuate his family from their homeworld when it was struck by a devastating plague. By the time he managed to reach out to his friend Bail Organa, it was tragically too late. From that moment forward, Durane made a solemn vow to himself that he would never again be poor or beholden to anyone.
Years later, Organa enlisted Durane's services to train his daughter, Leia, who was then serving her inaugural term as an Imperial senator, in the skills necessary to defend herself with weaponry. Despite the limited financial gain, Durane accepted the proposition out of a sense of obligation to his friend Organa. Upon Leia's arrival on the planet Challon, she encountered Giles and his associate, Gimlet, and the pair promptly intervened to thwart an assassination attempt on Leia's life. As Durane elucidated the reasons for his hiring, Leia initially displayed some reluctance, given her upbringing on the pacifistic world of Alderaan. However, it became evident that her life was in jeopardy, and as Durane pointed out, "not all matters can be resolved through senatorial debate." During his tenure serving the senator, Durane received the designation of Royal Weapons Master.

Durane brought Leia aboard his vessel and provided her with instruction in a diverse array of weapons, ranging from a handheld blaster to the ship's laser cannons. After a certain period, Durane conferred with Bail, and both reached the consensus that Leia had attained sufficient skill to defend herself, although Giles believed she could benefit from enhanced "speed and accuracy." As Leia continued her senatorial duties on Challon, General Emir, the mastermind behind the unsuccessful assassination attempts on Leia's life, came to the realization that he had engaged the wrong assassins. He determined that the individual responsible for eliminating his assassins was the only one capable of assassinating the senator. Consequently, he contracted Durane to eliminate Torgas, the leader of the Assassins Guild, and to complete his task by assassinating the senator.
Despite Durane's warning to Gimlet against alerting Leia, his partner attempted to do so regardless. However, Torgas arrived beforehand and fatally wounded Gimlet just as he approached Leia. As a result, when Durane appeared with the intention of killing Torgas, Leia initially believed she was safe—only to be informed by Durane of his new assignment. Having fulfilled his debt to Bail Organa, he had reverted to being a pure mercenary, committed to carrying out his contracted task, irrespective of the circumstances. However, when Durane discharged his blaster at Leia, she evaded the shot and retaliated, delivering a fatal blast with a speed and accuracy she had never previously achieved. Durane dropped his blaster and collapsed to the ground. With his final breath, Durane conveyed to Leia that he had always known that, under the right conditions, she would execute it perfectly.
Giles Durane was known as a man of jovial nature. During the Clone Wars, he was an idealist, but he became more cynical after a plague struck his homeworld, resulting in the death of his family and leaving him impoverished. Durane resolved to become self-reliant and avoid being indebted to anyone. As a mercenary, Durane was known for his incorruptibility, always prioritizing his assigned task.
Still feeling indebted to Bail Organa for saving his life many years prior, Durane agreed to train Leia Organa in the use of weaponry for self-defense. The skills he imparted to her proved invaluable—after his debt was settled, Durane accepted a contract to assassinate Leia, only to be killed by her own swift counterattack. He passed away as a man filled with pride in the skilled young woman he had trained.
In accordance with his title, the Weapons Master possessed a wide array of diverse weaponry. Among the most conspicuous were two light blasters, one positioned at his right hip and the other in a cross-draw rig beneath his left arm. Additionally, Durane wore a discreet, wrist-mounted dart launcher on his right wrist, capable of silently firing explosive or poison-tipped darts with a mere gesture of his hand. Along the left sleeve of his unassuming hooded jumpsuit, there was a row of small throwing discs, which Durane could wield with equally lethal precision. In a boot sheath, Durane kept an impressively large throwing dagger that he could draw with remarkable speed, thanks to a magnetic attractor concealed within his gauntlet.
The Weapons Master also carried a multipurpose scanner capable of detecting the presence of concealed explosives, as well as monitoring the remote systems aboard his personal vessel.

Giles Durane's character was conceived by writer Archie Goodwin and artists Carmine Infantino and Steve Mitchell for the narrative The Weapons Master!, which was initially published in Marvel UK's Star Wars Weekly 104–106 and subsequently reprinted in Marvel Illustrated Books' Star Wars. Durane also makes an appearance in the comic story "The Princess Leia Diaries" featured in Star Wars Tales 11, but his portrayal differs significantly from that in The Weapons Master!, where he is depicted as a much smaller man with darker skin, rather than the imposing figure seen in the former.