Master Tengen, often referred to as Tengen-sama, is a supporting character in the Jujutsu Kaisen series. They are a Jujustu Sorcerer and an immortal entity who has been around for centuries. Tengen is responsible for passing down the Jujutsu fundamentals to younger generations, which gave rise to the contemporary Jujutsu society and techniques we know of. They are also in charge of reinforcing protective barriers that protect both Jujutsu High locations. Tengens role and their Immortality technique are vital for passing down and protecting Jujutsu. Tengen is viewed as a pillar of security within the Jujutsu community but is not known for much beyond protection. Tengens whereabouts and current status are unknown, but JJK creator Gege Akutami did reveal Kenjakus plan for Tengen. Tengens Immortality technique grants them eternal life, but their body wears down and ages. If they dont find a new vessel every 500 years, Tengens body will try to force itself to find a new vessel. In 2006, Tengen was set to merge with a young girl named Riko Amanai, but she was killed by the Time Vessel Association before the merge could take place. Because the merge never happened, Tengens physical appearance began to evolve, so now they have four eyes, no hair, and a cylindrical head.