The “heart” of a lightsaber, the very thing that gives laser swords power, is a kyber crystal. They are special, extremely rare Force-sensitive gems inherently full of light side energy only found on a few planets in the galaxy far, far away. They even have their own kind of mystical sentience. Despite the weapons they create, though, kyber crystals have no color. They are naturally clear and only take on a specific hue when “ first attuned and connected to a Jedi.” Star Wars fans know that while a Jedi’s lightsaber can be anything from blue green, orange, purple, or yellow, every dark side users’ turns red.
That’s because Sith and Ren alike bend kyber crystals to their sinister side of the Force. That process is known as “bleeding.” And The Acolyte‘s season finale finally let us see a bleeding lightsaber happen in live-action.
Osha fell to the dark side during The Acolyte‘s eighth episode. She finally learned the truth about what the Jedi did to her coven on Brendok long ago. Full of rage and pain, Osha responded by Force choking Sol, her former Master who had lied about killing her mother. As she murdered him Osha held the Jedi’s lightsaber hilt. As the life drained from Sol’s body we saw one of the most notorious moments in the entire franchise. His blue kyber began to bleed. Osha was dominating it, turning the crystal red as she turned to the dark side.
After he died Osha turned to attack Qimir who had had put a hand on her shoulder. She turned Sol’s lightsaber on. It was blue at first, but it’s light changed to the signature red of evil. It did not do so without a fight though. The crystal tried to maintain its hold to the light side of the Force. In the end Osha’s new allegiance won out, as Sol’s lightsaber turned for good. When it did his former Padawan had left the light side of the Force completely.
It was a powerful, shocking moment, an incredible piece of Star Wars lore come to life. It’s something no Star Wars fan has ever seen happen on screen. Before The Acolyte, the process of bleeding a kyber crysta was only ever shown in Star Wars comics. The bleeding of a lightsaber happened in both Charles Soule stories about Darth Vader and Kylo Ren. Yet, for as cool as it was it was also terrible to watch. It was the physical embodiment of darkness corrupting a soul.
Kyber crystals aren’t just special rocks. Neither are they just a power source for a weapon. They’re an important part of the Force, both to themselves and as a tangible representation of the person who bonded with it. One that turned red are sad reminders of the fate that can befall even great heroes. Actually seeing that happen was an unforgettable reminder of the line thin between good and evil.
Mikey Walsh is a staff writer at Nerdist who spent decades waiting for Darth Plagueis to show up. You can follow him on Twitter and Bluesky at @burgermike. And also anywhere someone is ranking the Targaryen kings.