Completing the Sanctum of Temperance puzzle in Crimson Desert first requires you to unlock the Witch faction questline in Chapter 3's main quest. These vendors let you slot Abyss Gears, but they also unlock all of the sanctum puzzles across Hernand, letting you actually engage with them versus it just giving you a message that you first have to "meet a certain someone" when you approach them.
This one is pretty similar to the others in the region, so here's each step you need to take to cleanse the sanctum and keep those witches happy.
