It can be bought in Character Creation for 8,000 Gold for each individual character after completing Story Mode with that character. The stats of the weapon are different for each character. For Darth Vader, it has Soul Gauge Vamp equipped by default as a skill, which randomly decreases the opponent's Soul Gauge and allows the player to absorb part of it by pressing ++ simultaneously during battle. For The Apprentice, it has Invisible equipped by default as a skill, which allows the player to invisible for a certain amount of time by pressing ++ simultaneously during battle. And for Yoda, it has Guard Breaker equipped by default as a skill, which turns all high-attack-power moves into Guard Breaks for a certain amount time by pressing ++ simultaneously during battle.
Trivia[]
The "Forn" in the Lightsaber's name comes from the Aurebesh writing system that has been featured in various Star Wars media.