Customizing your lightsaber allows you to put your own individual stamp on your version of Cal, Jedi: Fallen Order's hero. ... It's important to note that lightsaber customizations don't actually have any gameplay value though, as it's strictly cosmetic. It doesn't improve your damage or combat abilities in any way.

Would lightsabers actually work?

A real lightsaber. ... Did #Disney invent a real working #lightsaber? Yes they did. It won't melt through metal blast doors, or cut off your hand, but it does feature an illuminated blade that will extend and retract at the push of a button.

Are lightsaber upgrades cosmetic?

Cosmetic. You can get an upgrade later on though that'll change it up a bit but otherwise mostly just cosmetic.