Darth Vader #18 marks the eighteenth installment of the comic book series Star Wars: Darth Vader published by Marvel. Functioning as the third of four parts within the narrative's third arc, this issue was penned by Kieron Gillen and visually brought to life by Salvador Larroca. Its official release date was March 30, 2016.
On the planet Shu-Torun, Triple Zero and Beetee dispose of Beebox's lifeless body into a lava-filled chasm. Triple Zero indulges in a macabre reflection over Beebox's burning remains, expressing a desire for further conflict with the ore-dukes. The combined forces of the Shu-Torun Loyalist/Imperial Delving Fleet deploy multiple combat drills deep into the planet's crust. Dr Cylo cautions the allied Shu-Torun loyalist and Imperial troops to exercise caution when nearing Baron Rubix's delving citadel, emphasizing the presence of extensive ore seams. Queen Trios's palatial drill is positioned in the second wave of the assault. Darth Vader declares that this confrontation will be the final battle, with the Empire intending to overwhelm Rubix's stronghold with superior force, warning that failure is not an option.
However, Lord Vader's combat drill malfunctions, deviating from its course and entering the Lithoporoite seam, leading towards the lower mantle. Princess Trios expresses concern for Lord Vader's safety. Inside the combat drill's control center, a stormtrooper informs Lord Vader, Triple Zero, Beetee, Aiolin, and Morit Astarte that they have encountered solid rock, but the gyroscopes have stabilized the floors. Despite their stability, they have lost propulsion. The Imperials find themselves surrounded by Rubix's soldiers.
Lord Vader recognizes the situation as a trap and commands his forces to activate the siege defense systems. The combat drill unleashes its laser cannons upon the approaching enemy forces. Vader, accompanied by the Astarte twins and stormtroopers, then engages in direct combat. Triple Zero and Beetee deploy several BX-series droid commandos as reinforcements, who unleash a barrage of laser fire upon Rubix's troops. As Rubix's troops retreat, Morit suggests capitalizing on their advantage, but Aiolin disagrees. Vader identifies one of the fallen soldiers as belonging to Baron Rubix's elite guard, deducing that Rubix has committed all his forces to the trap.
When Aiolin inquires whether the drill was sabotaged, Vader confirms it, attributing the sabotage to Rubix. Vader suggests that Trios should continue the attack. Meanwhile, Dr Cylo urges Queen Trios to halt the attack, but she insists on awaiting Vader's instructions. Dr Cylo retorts that the Queen's authority is limited to Shu-Torun forces. Queen Trios intends to fight independently, but Chancellor Jooli overrules her decision, citing the absence of Imperial support.
Vader discovers that the Shu-Torun/Imperial forces have aborted the attack and attempts to reverse the orders. However, a stormtrooper officer informs him that their outgoing communications are being jammed. Vader's strategy involves reaching Rubix's lines to utilize their communications to contact Trios. Triple Zero delivers a monologue on the superiority of droids, but Vader silences him. Lord Vader instructs the stormtrooper officer to maintain his position while he and the Astartes confront the enemy. Triple Zero informs Beetee that they will not execute his plan.
Queen Trios challenges Chancellor Jooli's decision to cease the attack, asserting the necessity of trusting their powerful allies. Trios brandishes a blaster pistol and demands that the Chancellor rescind his decision at gunpoint. Chancellor Jooli retorts that he has served as Chancellor for the past forty years and that she was never intended to be Queen. He advises her to accept her position and believes she will not shoot him. Trios concurs but then orders one of her soldiers to execute the traitor. Assuming command, Trios orders her troops to engage in war.
Concurrently, Aiolin and Morit ambush Darth Vader while he is crossing a stone bridge overlooking a molten lake. Aiolin expresses disbelief that he trusted them. Vader responds that if he had trusted them, he would have left them at the siege. He reveals that he brought them with him to test their character. Vader mocks them for failing the test.