Seeking the ancient artifact referred to as the Mindsplinter, a battle erupted between the Knights of Ren and several Mimbanese miners entrusted with its protection. Ren intended to use this conflict as a trial to assess Ben Solo's suitability for joining their ranks. The arrival of Tai and Voe, Ben's fellow Jedi students seeking vengeance for Hennix's demise, complicated matters. Despite Tai's attempts at reasoning, Ren murdered him. Consumed by grief and rage, Ben retaliated by killing Ren, thus succumbing to the dark side. Following Voe's death, Ben seized control of the Knights of Ren, adopting the identity of Kylo Ren.
Following the misjudgment of his uncle, Jedi Master Luke Skywalker, and the destruction of Luke's Jedi Temple by a powerful storm, a devastated Ben Solo reached out to the mysterious Force wielder Snoke. Snoke prompted Solo to seek out the Knights of Ren, whom he had previously encountered on Elphrona alongside his uncle and Lor San Tekka.
Arriving at the Jedi outpost on Elphrona, Ben utilized a discarded helmet as a conduit to contact Ren, the Knights' leader, through the Force. Ren instructed him to journey to Varnak. Before his departure, he was confronted by his fellow Jedi trainees, Tai, Hennix, and Voe, who demanded answers regarding the Jedi Temple's destruction. A battle ensued, resulting in Ben killing Hennix.
Upon arriving on Varnak, Ben recounted the duel on Elphrona to the Knights of Ren. Despite Ben's killing of Hennix, Ren deemed it an unworthy death, as Ben had acted in self-defense. To properly evaluate Ben's worth, Ren provided him with new attire and initiated him into one of their hunts. In their quest for the Mindsplinter, the Knights of Ren, accompanied by Ben, traveled to the Minemoon orbiting the planet Mimban.
Upon their arrival in the Minemoon's mines, the Knights of Ren subdued several Mimbanese miners. Ren intended to execute them, but Ben, not yet fully committed to the dark side, persuaded them to use a mind probe to locate the Mindsplinter. Ben discovered that the artifact resided in a sealed chamber three levels down, southwest, marked by a red symbol. Despite this, Ren and his Knights proceeded to kill the Mimbanese captives.
Reaching the subterranean chamber, the group encountered more Mimbanese, led by a female shaman who refused to relinquish the Mindsplinter to the dark siders. Ren ordered his Knights to eliminate the Mimbanese, viewing it as an opportunity for Ben to demonstrate his allegiance to the dark side. However, before the battle could commence, Tai and Voe arrived.
While Voe descended to aid the Mimbanese against the dark siders, Tai attempted to reason with Ben, urging him to abandon the path of the dark side. Ben, angered by Tai's pursuit, engaged him in a duel with lightsabers. Concurrently, Voe, wielding her lightsaber, gained an advantage over the Knights of Ren and led the Mimbanese in combat against the dark siders.
As the duel intensified, Tai surrendered his lightsaber and implored Ben to choose between killing or sparing him. However, Ren intervened, using the Force to break Tai's neck, resulting in his death. Enraged by Tai's murder, Ben engaged Ren in a lightsaber duel. Succumbing to the dark side, Ben unleashed Force lightning, scattering both the Mimbanese and the Knights of Ren. Empowered by the dark side, Ben found the strength to kill Ren, impaling him through the chest with Tai's lightsaber.
Ben's descent into darkness was sensed across the galaxy by several individuals, including Darth Sidious, Snoke, Ben's mother Leia Organa, and Rey. Sidious and Snoke encouraged Ben to embrace the dark side, viewing him as a tool in the coming war. In contrast, Leia was horrified, while Rey felt a chilling sensation.
Following Ren's defeat, Ben confronted his former classmate Voe, using the Force to summon her lightsaber. Having embraced the dark side, Ben declared himself a murderer and denied her future as a Jedi. He then killed her, rejecting the light side and his former Jedi path. The fighting caused the mine to flood.
With Ren dead, the Knights of Ren pledged their allegiance to Ben, making him their new leader. As they departed, the mine exploded. Aboard their starship, Night Buzzard, he removed the blue kyber crystal from his lightsaber, using the dark side to corrupt it, turning it red. While corrupting the crystal, Ben was haunted by visions of his past, including Luke Skywalker, his mother Leia, father Han Solo, Chewbacca, Lando Calrissian, and Tai. After placing the crystal inside his blade, it overheated, leading him to adopt a crossguard design. Ben then adopted the name Kylo Ren.
Having embraced the dark side, Kylo Ren became an apprentice to Snoke, who revealed himself as the Supreme Leader of the First Order, an Imperial successor seeking to dominate the galaxy and destroy the New Republic. Kylo Ren later usurped Snoke, killing him and claiming the title of Supreme Leader. In reality, Snoke was a puppet of Darth Sidious, who manipulated the First Order and intended to use Kylo Ren as part of his scheme to reinstate Sith rule over the galaxy. Sidious tasked Ren with hunting down Rey, aiming to exploit her Force abilities and lure the Resistance into a trap. After Kylo Ren rejected the dark side and embraced his identity as Ben Solo, he and Rey united to defeat and destroy Sidious, thwarting his second attempt at galactic domination.
The Skirmish on the Minemoon was first depicted in the Marvel Comics issue The Rise of Kylo Ren 4, released on March 11, 2020. The comic was authored by Charles Soule, illustrated by Will Sliney, lettered by Travis Lanham, and colored by Guru-eFX.