The Abyss of Ruh existed as a natural formation within the Rift of the world Tython, situated in the Deep Core region of the galaxy.
This vast and enigmatic natural chasm, known as the Abyss of Ruh, acted as a vergence projecting the influence of the dark side of the Force. It was located deep within the Rift on Tython. The Je'daii Order made their home on the planet, studying these unusual locations and trying to understand the world's secrets. While the Rift was a kilometer in depth in some locations, the Abyss seemed to have no bottom, as attempts to measure it failed. This area presented many dangers, such as acid pits, volcanoes, and quicksand. Unique and uncommon creatures lived deep within the Abyss, found nowhere else. Some Je'daii thought the Kwa had built underground tunnels connecting the Abyss to the Chasm many kilometers away. Entering the Abyss was very dangerous. Its energies could interfere with mechanical sensors and flying technology, and those strong with the Force would suffer from intense hallucinations.
The Je'daii Ranger Rian Ruh discovered this location, and it was named in his honor after he lost his sanity exploring it. Je'daii ventured into the Abyss, a perilous and forbidden zone, in groups sent from Anil Kesh to capture the strange beasts that appeared there for study. During the Great Journey of [Dalien Brock](/article/dalien_brock], supervised by a Je'daii Temple Master, Brock disobeyed orders and fled into the Abyss, emerging changed and corrupted. Upon his return to Anil Kesh with the wounded Je'daii Journeyers who had attempted to rescue him, he murdered Journeyer Skott Yun by shooting him, and then escaped into the night.
After the Devourer crashed in 25,793 BBY, Xesh, a Force Hound of the Infinite Empire, came out of the wreckage and escaped into the Abyss of Ruh. The numerous deaths from the crash made the Je'daii aware of the foreign presence, and also triggered a huge Force storm that spread across Tython. The Je'daii Journeyers Shae Koda, Tasha Ryo, and Sek'nos Rath received a vision from Xesh warning them of the crash, and they immediately went to the Rift to investigate. Arriving at the crash site, they examined the wreckage of the alien ship and found an escape pod with the stranger from their vision: the Force Hound Xesh. The three Je'daii chased the Force Hound into the Abyss, and suffered hallucinations from the dark energies in the volcanic landscape. Working together, the trio overcame the effects and found Xesh fighting a saarl. The trio made a final stand and tried to defeat the beast, but they could not activate the Forcesaber Koda had taken from Xesh. Koda gave the saber back to Xesh at the urging of her companions, and he killed the worm. Soon after, the Je'daii Master Quan-Jang arrived, having concluded that Xesh was causing the storm threatening Tython, and struck him down with lightning so Rangers Hawk Ryo and Rori Fenn could arrest him. Quan-Jang, with telepathic support from the other Temple Masters, rose above the Abyss and used the Force to stop the Force Storm.