Null Blade

The Null Blade was a sword forged with cortosis alloy by Miril, the leader of the anti-Sith Ascendant cult during the era of the Sith. As a cortosis weapon, the blade could short out a lightsaber for a brief time if the lightsaber blade made contact with the Null Blade. However, as the weapon was not reinforced by Miril by the time of the fall of the Ascendant, the Null Blade itself would be cut by the lightsaber: in effect, Miril had a weapon that could be cut down by a lightsaber, only for that lightsaber to then fail. Centuries later, the Spark Eternal—a creation of Miril and the Ascendant—resurfaced and possessed the body of Doctor Chelli Lona Aphra, who it used to wield the Null Blade after rediscovering the weapon. With the blade able to take on lightsaber strikes by that time, the Spark-possessed Aphra wielded the Null Blade against the Sith Lord Darth Vader during the Battle at Amaxine Station, where the possessed doctor shorted out Vader's blade once their weapons struck each other. In response, Vader unleashed a Force push that separated Aphra and the Spark.

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