One of the signature powers of the Sith seen throughout various Star Wars media is Force Lightning, so it seems odd that Darth Vader, the greatest wielder of the Dark Side, never used it. In the past, the common explanation has been that it cannot be channeled through his robotic limbs, but it has now been explained that Vader possesses the power, but it’s too dangerous for him to use, with it coming down to his lightsaber.