Duel on Kalakar Six

In 0 BBY, a duel was fought on the moon Kalakar Six between the Sith Lords Darth Vader and Darth Maul. Maul was previously defeated decades prior to the duel by the Jedi Obi-Wan Kenobi, who then took Anakin Skywalker, the boy who would become Vader, as his Padawan. Skywalker was eventually lured to the dark side of the Force by Maul's master Darth Sidious, who was also known publcly as Emperor Palpatine. By 0 BBY, three dark side adherents believed that a remnant of the light side remained in Vader, and that he was a threat to the future of the dark side. They either resurrected, cloned, or conjured a vision of Maul for the purpose of fighting Vader and lured him to Kalakar Six through false intelligence concerning the Death Star plans, which had been recently stolen by the Alliance to Restore the Republic.

Vader arrived on the volcanic moon with a unit of eight stormtroopers and entered a fortress to search for the plans. Maul and the adherents killed all of the stormtroopers, after which they revealed themselves to Vader, accused him of being an unfit apprentice to the Emperor, and challenged him to duel Maul. They began to fight with their lightsabers, with Vader using the Force to fire his dead trooper's rifles at Maul, and Maul attempting to knock Vader into the lava pit below them. Both combatants taunted each other throughout the duel, with Vader calling Maul an imposter and Maul claiming that Vader had too much of the light side in him to overcome Maul's hatred.

The duel proceeded to a rock platform floating in the magma, where Vader sliced through Maul's double-bladed lightsaber and Maul damaged Vader's helmet, knocking the cyborg Sith to his knees. As Maul stood behind Vader and prepared to strike a killing blow, Vader aimed his lightsaber into his own body, fatally stabbing Maul. In his last moments, Maul asked what Vader could hate enough to have defeated him, and Vader responded that it was himself. The adherents were shocked at their defeat and nearly struck down by Vader, but were instead killed by Palpatine, who had arrived at the fortress. Vader departed the moon to continue seeking the Death Star plans, and would ultimately return to the light and betray the Emperor, leading to both of their deaths.

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