Lightsabers

The lightsaber is the fictional weapon of the Jedi Knights in George Lucas' Star Wars. It is a blade of pure energy that cuts through just about anything.
The energy blade is highly focused plasma that is held in shape by an electro-magnetic field.
Lightsabers can only be constructed by Jedi, and it is a long and difficult process, requiring intense concentration over many days. During the Clone Wars, certain elite Jedi Masters could construct tempory lightsabers in minutes.
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