Galen Marek's lightsaber

This red-bladed lightsaber was the Sith weapon of the Dark Lord Darth Vader's secret apprentice, Galen Marek, a Force-sensitive assassin codenamed Starkiller. The apprentice's lightsaber was of a skeletal and utilitarian design. Intended for both training and combat purposes, it served multiple purposes such as the many sparring matches between the apprentice and his holodroid PROXY, as well as meditation sessions in which he concentrated on telekinetically re-assembling his lightsaber for modifications.

As his training neared completion by 3 BBY, the apprentice was dispatched on a series of tasks to assassinate three fugitive Jedi Masters—Rahm Kota, Kazdan Paratus and Shaak Ti. Upon the completion of his final trials, Vader betrayed his apprentice on the orders of Emperor Palpatine, and cast him out into space. As a result, Marek's lightsaber was lost in the vacuum of space, though he was ultimately saved from death by his Sith Master in order to be redeployed on several new missions that would lead to the formation of the Rebel Alliance. Due to the loss of his apprentice's lightsaber, Darth Vader provided Marek with another lightsaber as a replacement.

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