Kylo Ren was a Force-sensitive human male who trained as a Jedi pupil under Jedi Master Luke Skywalker before turning to the dark side of the Force and joining the Knights of Ren. He was born with the name Ben to Princess Leia Organa and the smuggler Han Solo. In his youth, he displayed traits similar to that of his grandfather, Anakin Skywalker, who had turned to the dark side and became the Sith Lord Darth Vader. Ben, who was sent by Organa to be trained by his uncle, fell under the influence of Supreme Leader Snoke of the First Order and destroyed the new generation of Jedi that Luke Skywalker was training. Skywalker vanished, while Ben took the name Kylo Ren and joined the First Order. His goal was to complete what Darth Vader once started and destroy the Jedi.

Years later, Ren sought the remaining fragment he needed to build a map that would lead to Skywalker's location, so the last Jedi could be destroyed. Ren hunted the astromech droid, BB-8, who carried the map and tracked the droid to Takodana after learning that the droid was in the possession of Han Solo. There, Ren also discovered Rey, a Force-sensitive who had seen the map and was helping BB-8 bring the map to the Resistance. Ren brought Rey to Starkiller Base, a First Order stronghold and superweapon, and attempted to probe her mind for the map information, but she resisted and escaped. The Resistance soon attacked the Starkiller weapon to destroy it, and Ren encountered Solo once again during the battle. He killed his father, hoping to eliminate the light that Ren struggled with inside himself, and tracked Rey and the fugitive stormtrooper Finn to a forest as the Starkiller was under siege. He engaged both in a lightsaber duel, besting Finn before being beaten and injured by Rey. As the Starkiller began to implode from the Resistance attack, Supreme Leader Snoke ordered General Hux, the base's commander, to bring Ren before him so his training could be completed.

Darth Vader's group
Luke Skywalker's group
Obi-Wan Kenobi (jedi) group