During the Clone Wars, the rogue Sith Lord Maul commanded a criminal organization known as the Shadow Collective to seize control over the planet of Mandalore. During a conflict within the city of Sundari, Maul was apprehended by his former Sith Master, Darth Sidious, who subsequently imprisoned Maul in the Spire, a Separatist detention center located on Stygeon Prime. Mandalorian super commandos Rook Kast and Gar Saxon of Death Watch, affiliated with the Shadow Collective, trailed Sidious' vessel, acting under the directives of Prime Minister Almec of Mandalore. Their objective was to ensure Maul's liberation from the Spire.
Sidious, alongside his apprentice, Count Dooku, orchestrated Maul's escape, with the intention that he would guide them to the Nightsister witch Mother Talzin, Maul's mother and a long-standing adversary of Darth Sidious. Dooku briefly interrogated and inflicted torture upon Maul to extract information regarding the Shadow Collective, leading the rebellious Sith Lord to believe that his adversaries sought only to dismantle his power base. Following the interrogation, the Mandalorians launched an assault on the prison and successfully rescued their captured leader, subsequently reuniting with the remaining forces on the moon of Zanbar. Maul's breakout triggered a battle on Zanbar involving Death Watch and the Separatists, setting off a series of events that ultimately resulted in Talzin's demise and the downfall of Maul's Shadow Collective.
During the era of the Clone Wars, and exceeding a decade past his presumed death during the Battle of Naboo, the Sith Lord known as Maul resurfaced as a prominent figure within the galaxy by establishing a criminal enterprise called the Shadow Collective. This organization—comprising Death Watch, a splinter group of Mandalorians; the Pyke Syndicate, the primary distributors of spice in the galaxy; and the Hutt Clan—initiated a coup aimed at overthrowing Duchess Satine Kryze and her pacifist government on the planet of Mandalore. This action fulfilled Death Watch's long-term ambition to seize control of the planet and reinstate Mandalore's ancient warrior traditions, which had been superseded by the pacifistic principles espoused by Duchess Kryze and the New Mandalorians. With Death Watch in command of Mandalore, Maul wrested power from the Death Watch leader, Pre Vizsla. Numerous Death Watch loyalists then opposed Maul, leading him to form his own group of Mandalorian super commandos. The ensuing conflict resulting from Maul's power grab culminated in a battle within the capital city of Sundari, where Darth Sidious—Maul's former Sith Master—arrived and captured Maul during a lightsaber duel. Sidious revealed to Maul that he had no intention of killing his former apprentice, as he still had use for Maul; it was Sidious' hope that Maul would lead the Sith to Mother Talzin, Maul's mother and the leader of the Nightsisters, so she could be eliminated as a potential threat to the eventual Sith rule of the galaxy.
Sidious transported Maul to the Spire, a fortified prison under the control of the Confederacy of Independent Systems situated on Stygeon Prime. It was at this location that Sidious briefly interrogated Maul, instructing Count Dooku, his apprentice, to extract information regarding the identities and locations of the Shadow Collective's leaders. The objective was to deceive Maul into believing that the Sith intended to dismantle the Shadow Collective, thereby prompting him to seek out Mother Talzin. Concurrently, Sidious was followed to Stygeon Prime by two Death Watch warriors, Rook Kast and Gar Saxon, acting under the orders of Mandalore's Prime Minister, Almec, with the mission to liberate Maul from the Spire.
Upon infiltrating the Spire, and while Dooku was interrogating Maul to gain intel on the Shadow Collective, Kast and Saxon established contact with Almec. Saxon informed the Prime Minister that they had pinpointed Maul's location on the prison's seventh level. Almec authorized their mission, and the pair detonated explosive devices on the third level of the prison as a means of creating a diversion. Battle droids were dispatched to the third level to investigate the explosion, although Dooku suspected that Maul was the actual target of the assault. Droidekas were deployed to the seventh level, where the two Mandalorians used electromagnetic explosives to disable super battle droids.
As they drew closer to Maul's cell, Kast and Saxon neutralized the droidekas using a rocket, eliminating them and securing the path to the cell. Upon reaching Maul, they released him from his restraints and informed him of their arrival to facilitate his rescue. They launched another rocket through the prison's walls, and the three escapees descended via zipline out of the fortress, traversing the mountains to reach the surface, where a contingent of battle droids opted not to pursue them. Meeting minimal resistance, intentionally designed to enable Maul's escape, the three boarded a Death Watch Gauntlet fighter and took off. Before departing Stygeon Prime, the fighter fired back at the prison, destroying the battle droids that had chosen not to give chase.
Kast and Saxon transported Maul to Zanbar as instructed, where the Death Watch leader was reunited with his forces. They were subsequently pursued by the Separatists, led by General Grievous—who was under explicit orders to weaken, but not eliminate Maul, with the intention of compelling him to seek assistance from Mother Talzin against the Sith. The two armies clashed on Zanbar, and by the conclusion of the battle, Maul issued an order for his forces to retreat. As Sidious and Dooku had anticipated, Maul contacted Mother Talzin, who instructed him to re-engage the Separatists in combat on Ord Mantell. During the subsequent battle, Maul captured Dooku and Grievous, leading to a temporary alliance between Maul and Dooku when confronted by the forces of the Grand Army of the Republic. This alliance was a component of Sidious's strategy, a fact of which Maul was also aware.
During the Siege of Mandalore, Maul addressed Saxon, Kast, and several other warriors, referencing the occasion when they had freed him from Dooku's captivity. Although he had initially perceived Dooku as foolish, he subsequently realized that they were alike—both being manipulated by Sidious. Maul then conveyed his perception that the dark side was at its zenith and rallied the Mandalorians to prepare for combat.
Maul's escape from the Spire was depicted in the comic book titled Darth Maul—Son of Dathomir 1, authored by Jeremy Barlow and published by Dark Horse Comics on May 21st, 2014. At the time of publication, the prison lacked a formal name, but it was later designated as the "Spire" in Star Wars Rebels: The Visual Guide.