The Acolyte’s Mysterious Lightsaber Stopping Metal Explained

I first discovered cortosis when I played the legendary Star Wars RPG Knights of the Old Republic—KOTOR if you’re nasty. The game didn’t want you to have a lightsaber immediately, but it also wanted to make melee combat against the Sith with a viable option.

The solution? Cortosis swords.

In fact, cortosis weapons showed up in lots of different places in Legends continuity. Like with many things in Star Wars, these appearances often contradict each other. In KOTOR, cortosis is capable of blocking lightsaber blades but does nothing to alter their functionality.

The metal is described in the novel Darth Bane: Path of Destruction as “incredibly dense and difficult to mine.” A description designed, no doubt, to preempt any trolls asking, “Why isn’t everything made with cortosis?”

Other Legends materials set after KOTOR and Bane described the metal as “brittle,” “highly malleable,” and, most importantly, capable of blocking lightsabers and causing them to short out on contact. When cortosis hit canon in 2014, it was even rarer and more unique. In one novel, Grand Admiral Thrawn states that cortosis is “soft and frangible, useless for building into armor or other protective materials.

Now, before anyone starts in on “See, The Acolyte doesn’t understand Star Wars! Darth Teeth had a cortosis helmet and gauntlet!” In the same quote, Thrawn mentions that some have found a way to weave cortosis into a “protective matrix,” with other metal. In other words, you can mix cortosis with other metal and still get armor that can disable lightsabers.

However, this still isn’t a common practice, so don’t start complaining that everyone in Star Wars should wear cortosis armor. The Stranger’s cortosis helmet is a lot like the Holdo Maneuver from The Last Jedi. It’s not there to make you question why everyone is Star Wars isn’t using it.

It’s there to look cool and make your eyeballs pop out of your head.

The Stranger—as Disney officially calls Smilo Ren—also mentions that his particular cortosis helmet acts as a sensory deprivation helmet. Star Wars has often shown Jedi wearing headgear to shut off their senses, allowing the Force to guide their actions. As of writing this, there’s no indication that the lightsaber-disabling property of the cortosis and the fact that the helmet blocks the wearer’s senses are related in any way.

The Stranger also alludes to the helmet’s ability to block the Jedi’s telepathy. When Master Sol first suggests that The Stranger remove his mask, the Sith replies that doing so would let the Jedi read his thoughts. Masking one from the Jedi is not usually one of cortosis’ natural properties, leaving me to assume there is something special about The Stranger’s mask specifically.

So there you have it. If you come across a negative Nien Nunb complaining that Disney just keeps making stuff up like lightsaber-breaking armor, remind them that cortosis has been around since before the prequels, and it’s their IP so they can do whatever they want with it.