Force Lightning

Force Lightning is a well known Dark Side ability.

It is a purely energy-based attack used by the Sith. Force energy takes the form of lightning bolts which exit the force-user's body through his hands; force lightning can be executed with either one or two hands. The greater the user's aptitude, the more power the lightning bolts possess and the more they fork, allowing the possibility of striking multiple foes at once. This force-power is often used as a form of torture as it not only causes severe physical damage but also extreme agony to the victim. However, a single powerful blast may be sufficient to kill a person instantly. It is unclear why Palpatine kept electrocuting Luke Skywalker for so long. It is likely that Palpatine, harboring extreme antipathy toward the Jedi, sought to maximize the intensity and duration of Luke's suffering. Others maintain that the Emperor's force powers were, by that time, insufficiently strong to rapidly dispatch Skywalker.

Depending on the level of intensity, force lightning can apparently ground itself on an ignited lightsaber. Nevertheless, a sufficiently powerful force-user can blast through the defenses afforded by a lightsaber, as seen when Darth Sidious blows Jedi Master Yoda's lightsaber right out of his hand during their duel in the Senate chamber. Force lightning can also be absorbed and redirected by a Jedi of sufficient skill; Yoda demonstrated this ability by both reflecting and absorbing it during a fight with Count Dooku (probably Force Absorb). It appears that prolonged use of force lightning can drain the user physically, and could possibly result in severe deformations. This may have been when Darth Sidious unleashes a barrage of force lightning on Mace Windu, but has it reflected back upon him by the Jedi Master's lightsaber. Nevertheless, this view is controversial; it is thought by some that Sidious' physical appearance as Chancellor Palpatine was an illusion created with force energy, and that the lightning merely melted the illusion away.

Though a powerful Sith Lord, Darth Vader was unable to use force lightning for much of his reign, as both of his arms were mechanical for most of the time he was a Dark Sider