Darth Plagueis (pronounced /'pleɪɡ.əs/) was a Force-sensitive Muun male Dark Lord of the Sith and the Sith Master of Darth Sidious. Plagueis lusted for immortality, believing the secret laid in science. To that end, he worked with his Sith apprentice, conducting research into bioengineering and experimenting with his ability to influence the midi-chlorians to create life. In doing so, Plagueis acquired considerable knowledge of the Force, but he was ultimately betrayed and murdered by his own apprentice in accordance with the Rule of Two. Sidious later recounted the tale of his master's demise to lure the Jedi Knight Anakin Skywalker to the dark side of the Force, calling the fallen Sith Lord Darth Plagueis the Wise. After his own demise, Sidious used his master's teachings to cheat death, though true immortality still eluded him up until his final end.

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Can be used as Upgrade, units, spell abilities and some sort item like Cloak of Darkness or something.