Serenity

One of five mysterious beings called as the Force Priestesses, Serenity was a female being that lived on a mystical planet, known as the Wellspring of Life, at the center of the galaxy. Alongside her four other cousins, she was an avatar that embodied the connection between the Living Force and the timeless Cosmic Force. Mutable in her appearance, she was able to retain her consciousness following her physical death, acting in a serene way as opposed to her four other cousins, who symbolized the emotions of Anger, Joy, Sadness, and Confusion. Often the spokesperson for her cousins, Serenity granted individuals the necessary training in order to achieve the state of immortality, which the priestesses had deemed the "great gift," acting along with the coupled blessings of her cousins.

In 19 BBY, near the end of the Clone Wars, Serenity encountered Grand Master Yoda of the Jedi Order. To discover his worthiness of their teachings, she and her cousins presented him with a set of trials for the Jedi Master. Passing their given trials on their world, Serenity and the priestesses then sent him to the Sith homeworld of Moraband, to meet his final trials. Encountering obstacles that were of her creation, the Jedi Master then came across the Sith Lords Darth Sidious and Count Dooku. Ultimately overcoming the two Sith, Serenity deemed Yoda worthy of the immortal gift and that he will be trained by deceased Jedi Master Qui-Gon Jinn.