The lightsaber is a melee-based weapon used by the player in the Jedi Knight games. It is first given to the player at the beginning of level 4 in Jedi Knight, but is given right away at the beginning of Mysteries of the Sith.
The lightsaber is a close-range weapon, making it difficult to use. However, it is extremely powerful, being able to take down almost any ground enemy in one hit. It is also one of the only weapons capable of attacking ATSTs and Kell dragons, as those enemies deflect common blaster-fire.
The primary attack is a simple swing. Moving in a certain direction changes the direction of the swing. The direction of the swing is usually the opposite of the player movement. Holding primary fire down will create a rapid swing, which is faster but more uncontrolable. The secondary attack is a much wider, single swing. This takes longer to preform, but cause much more damage.