Kylo Ren's lightsaber

Kylo Ren's lightsaber was a crossguard lightsaber constructed sometime before or during the year 34 ABY by Kylo Ren, Supreme Leader of the First Order, and Master of the Knights of Ren. The lightsaber, based on an ancient design dating back to the Great Scourge of Malachor, contained a cracked Kyber crystal, requiring it to have lateral vents on either side of the handle in order to divert the extra heat generated by the crystal.

During the cold war, Ren used the lightsaber to strike down Lor San Tekka, a member of the Church of the Force. When his father, Han Solo beseeched him to leave the First Order, Ren ignited the crossguard lightsaber through Solo's chest in an act of patricide. He later dueled the former stormtrooper known as Finn, and the Force-sensitive scavenger Rey, though he lost to the latter.

Description
Kylo Ren, master of the Knights of Ren and Supreme Leader of the First Order, owned a crossguard lightsaber during his time as the dark side apprentice of former Supreme Leader Snoke. The weapon was built sometime before or during the year 34 ABY. The lightsaber was crudely assembled based on an ancient design dating back thousands of years to the Great Scourge of Malachor. Despite being an ancient design, the lightsaber had modern components inside it. A single cracked Kyber crystal, barely able to contain the weapon's power, necessitated the lateral vents which diverted the extra heat produced by the crystal to either side of the hilt, and gave the weapon's red plasma blades an unstable, serrated appearance. To balance the weapon's power, the crossguard blades emerge after the main blade appears.

History
"I'm being torn apart. I want to be free of this pain. I know what I have to do but I don't know if I have the strength to do it. Will you help me?''" "''Yes. Anything."

- Kylo Ren and Han Solo

Kylo Ren wielded the crossguard lightsaber while working alongside the Knights of Ren and the First Order. During the conflict between the First Order and the Resistance, he used the lightsaber to kill Lor San Tekka, a member of the Church of the Force, as well as his own father, Han Solo. It later crossed blades with the Skywalker lightsaber, a Jedi weapon that once belonged to Ren's grandfather, the Jedi Knight Anakin Skywalker. Although he defeated and injured the former stormtrooper known as Finn in a brief duel, he was in turn defeated by Rey, who successfully channeled the Force within herself to fight back, striking Ren's lightsaber and knocking it from his hand.

Despite the weapon being damaged, it was far from irreparable, as Kylo Ren would soon use the weapon again, adding a sleeker black casing to it. While in the presence of Snoke's Elite Praetorian Guards, the lightsaber came into the possession of Rey, who summoned it from Kylo's side in an attempt to fight Snoke and his bodyguards. In spite of her efforts, Rey was telekinetically disarmed by Snoke, who commanded his apprentice to kill the aspiring Jedi. Kylo used the moment as an opportunity to assassinate Snoke by cutting him in half with the Skywalker lightsaber. Activating his own lightsaber, Kylo Ren fought alongside Rey against the Praetorians, all of whom perished while attempting to avenge their slain leader. After the battle in the throne room, Kylo assumed the title of Supreme Leader and brought the forces of the First Order to the planet Crait, where he attempted to fight his uncle Luke Skywalker, only to discover that he was fighting a projection of the Jedi Master. As a result, the Resistance was able to escape before Ren could destroy them.

Behind the scenes
Kylo Ren's lightsaber was introduced in the first teaser trailer for Star Wars: Episode VII The Force Awakens. The trailer, released on November 28, 2014, showed Ren walking through a snowy forest on Starkiller Base and igniting the lightsaber. The introduction of the lightsaber was well-publicized in the media, including on The Colbert Report and @Midnight on Comedy Central. The lightsaber was also the subject of a number of pieces of fan art released in the days after the trailer premiered.

It appeared twice in the second trailer that debuted at Celebration Anaheim 2015. The trailer showed Ren swinging the lightsaber, and later holding it in his left hand while he holds out his right. The concept of a crossguard lightsaber was first introduced in Star Wars Legends, previously known as the Expanded Universe. The lightsaber, which had two beams rather than three, made its first appearance in the 2004 comic book Republic 61: Dead Ends.

Appearances

 * Star Wars Battlefront II
 * Star Wars: Episode VII The Force Awakens
 * Star Wars: The Force Awakens novelization
 * Star Wars: The Force Awakens: A Junior Novel
 * Star Wars Adventures: Forces of Destiny: Rey
 * Star Wars: The Force Awakens Graphic Novel Adaptation
 * The Force Awakens, Part I
 * The Force Awakens, Part II
 * The Force Awakens, Part IV
 * The Force Awakens, Part V
 * The Force Awakens, Part VI
 * The Force Awakens: Rey's Story
 * Star Wars: The Force Awakens Beginner Game
 * Captain Phasma, Part I
 * Poe Dameron: Flight Log
 * Star Wars: Episode VIII The Last Jedi
 * The Last Jedi: Rey's Journey
 * The Last Jedi: Rey's Journey

Non-canon appearances

 * Disney Infinity 3.0
 * LEGO Star Wars: The Force Awakens
 * Star Wars: Galaxy of Heroes