Duel on Ambria (980 BBY)

A duel between the Sith Master Darth Bane and his apprentice, Darth Zannah, took place on the planet Ambria in 980 BBY. Bane had begun to fear that Zannah was waiting to challenge him until he grew weak, violating the purpose of his Rule of Two to ensure that the apprentice took the title of Master only because the apprentice was stronger. Bane thus sought the secret of eternal life so that he could live to train another apprentice. Meanwhile, Zannah had finally made her own plans to confront Bane in an attempt to become the Master, and upon learning of his quest for eternal life, she felt as though he had betrayed his own Sith Order. She found and confronted him on the planet Doan, but the duel led to a draw. Bane found a new apprentice, the Iktotchi Darth Cognus, and messaged Zannah to come to Ambria and finish their fight. Upon Zannah's arrival, Cognus swore to serve the true master—whomever won the coming battle.

The duel began, and Bane instantly gained the upper hand, quickly forcing Zannah to give ground. She tripped while preparing to use a spell on him, and he cracked her rib before she was able to make an energy-draining escape. Zannah then attempted in vain to use sorcery to drive him insane and finally resorted to conjuring dark side tendrils from the ground. He charged her, hoping to strike her down before the tendrils hit him, but one connected with his arm and cut it off. Collapsing to the ground in pain, Bane grabbed Zannah and attempted to transfer himself into her body, using the technique he had learned in his search for eternal life. Her will was too strong, however, and after an intense mental battle she defeated him, casting his consciousness into oblivion—although part of Bane remained imprinted upon her. Zannah took from Bane the mantle of Dark Lord of the Sith and, with Cognus as her apprentice, continued the legacy of Bane's Sith Order and the Rule of Two.

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