In Episode 5 of The Acolyte, we came across cortosis.
This was the first live-action appearance of this metal. We saw that it could aid someone in battle quite effectively.
So, why isn’t cortosis used more often in Star Wars? It has been used in Legends but remains rare in Canon because of its rarity and potential ineffectiveness.
The Power of Cortosis
As Star Wars fans may know, cortosis is a rare metal with an extremely high “energy absorption rate” that can diffuse a blaster shot and deflect a lightsaber.
As one of the strongest minerals, cortosis can also short out a lightsaber blade and be used to stop a Jedi from being able to read their adversary’s thoughts, as shown in The Acolyte.
During the Old Republic, the Ascendant, a group who tapped into the dark side of the Force to battle against the Sith, made use of cortosis.
They created the Null Blade with cortosis, which could short out a lightsaber. Once the Sith rose in the High Republic, “the Stranger” or “the Master” had a gauntlet on his left arm and helmet made of cortosis.
As depicted in The Acolyte, this Master (alias Qimir) withstood lightsaber attacks and made several Jedi’s lightsabers short out when they fought in Episode 5.
Only lightsabers with kyber crystals from the planet Mestare are known to be resistant to its effects. The helmet worn by the Master is protective against lightsaber strikes but does falter after repeated blows, as also captured in this series.
Here we see Osha putting on the cortosis helmet in Episode 6, providing a sense of its foreboding power. As this article speculates, this helmet may be connected to the Sith Lord Darth Momin, including the power to corrupt its wearer to the dark side.
The helmet could sway Osha to the Sith side, and cortosis itself can stop lightsabers.
Why Isn’t Cortosis Used More Often?
Given the strengths of cortosis, it is puzzling that it is not used more frequently in Star Wars. The Acolyte is the first live-action show to integrate it.
Cortosis has a deeper history in Legends, starting with the 1998 novel I, Jedi, by Michael A. Stackpole, but not in Canon. One reason for this from this same article is that cortosis is so rare and only sourced from two main planets in the galaxy.
So, getting a hold of it and refining it would take much time and effort.
Another reason, going with the strength of this material, is that using cortosis provides such great power that lightsaber battles could be too short. Since cortosis can short out lightsabers, we might see short-lived lightsaber fights or too many Jedi perishing, as in The Acolyte.
Yet, as fans point out, using Cortosis in battle is not a sure victory because it only provides “an impossibly small window” to strike your opponent.
More skilled Force users will switch to another method of fighting, such as Darth Vader Forcing choking his adversary. In reverse, cortosis may be ineffective in battle depending on the opponent.
In addition, fans emphasize how cortosis is rare and fragile, unlike the strength of Beskar steel or Kyber crystals, which makes it problematic.
Another article adds that the Jedi did not use cortosis because they thought it was “a dishonorable way to fight” and usually did not encounter it because of its rareness.
Cortosis also became associated with the Sith and that would be counter to Jedi ways. In addition, after the Jedi-Sith War at the end of the Old Republic, the Jedi did not confront any Sith for about 1,000 years.
Cortosis in Star Wars
In Legends, cortosis was used by villains like the assassin Sajé Tasha and the bounty hunter Cad Bane in the Clone Wars.
During the Empire, the Jedi Shadday Potkin used a cortosis blade weapon to temporarily short out Darth Vader’s lightsaber in the comic Star Wars: Purge. Yet, we have not seen cortisis on-screen until The Acolyte.
We have not because of the rarity of this material, that it is primarily a dark side weapon, could lead to short lightsaber fights, or not be that effective in battle, as was the case against Vader.
Cortosis has several roadblocks to wider usage, but we will probably see more of it in The Acolyte.