A rocky planet was located in the Rarlech system of the Unknown Regions. Supreme Leader Snoke and his apprentice, Kylo Ren, traveled to the planet. There, Snoke taught Ren how to weaponize his rage before departing the planet to continue the training elsewhere.
A planet was located in the Rarlech system of the Unknown Regions, within grid square H-5 of the Standard Galactic Grid. Mountains, jagged tree-like rock formations, and cliffs existed on the planet's surface. It had a Type I breathable atmosphere in which lightning storms could form.
Sometime between 28 ABY and 34 ABY, First Order Supreme Leader Snoke traveled to the planet with his apprentice, Kylo Ren, during a lightning storm. Snoke pushed Ren off a cliff and suspended him in mid-air with the Force to make him feel powerless. The Supreme Leader then dropped Ren to the jagged rocks below, urging him to turn his fear into power. Ren caught himself by using the Force before impact while Snoke traversed down a stairwell to meet him. When Ren inquired if Snoke would have saved him if he had failed, Snoke replied that Luke Skywalker—Ren's former Jedi teacher—would have applied such training methods and that they would have made Ren weak. Snoke then led Ren to an Upsilon-class command shuttle to depart the planet and continue Ren's training on the Outer Rim planet Dagobah.
The planet first appeared in the comic one-shot issue Age of Resistance - Supreme Leader Snoke 1. The comic was written by Tom Taylor, illustrated by Leonard Kirk, and published by Marvel Comics on September 11, 2019.