The Trial of Spirit

To pass the Trial of the Spirit, apprentices had to look deep within their souls, on a quest of self-discovery. This test was designed to pit a potential Knight against their most dangerous enemy: the darkness within themselves. Often, apprentices did not like what they saw, and it could be a highly traumatic experience. Because of this grueling self-examination, this Trial was often known as Facing the Mirror. While bearing similarities to the Trial of Skill, this test did not involve moving at all in most cases; instead a Padawan delved deep into a meditative trance to combat their inner fears and demons. Because of the ultra-personal details of the test, it is one that not even the High Council dare dictate. A Padawan must write the script for what will transpire on the journey. Because of the dangers of such deep meditation, a Master was always present to help guide a student back after they pushed them past where they least desired to go in their thoughts. The worst that could happen following a failed trial is awakening from meditation screaming and mentally broken.
Throughout the final days of the Order, the test was taken by several thousand Jedi. Whether facing visions of nexu or dangerous foes, the test always proved extremely emotionally trying. While not quite orthodox, the High Council acknowledged that Anakin Skywalker had indeed passed the Trial (in the spiritual throes of a cavernous Force vision antecedent to a heroic tribal rescue) while on Nelvaan in 13 ArS. There, on a mission, Skywalker fell into deep meditation and saw himself as Darth Vader, his future incarnation as Dark Lord of the Sith. Several decades later, Skywalker's own son, Luke, would be urged to take on the same trial on the swamp world of Dagobah. As per tradition, the exiled Grand Master Yoda observed the test from nearby, as young Skywalker entered the mysterious cave that cropped out of the muck. Inside, Skywalker dueled briefly with his father, Darth Vader, before removing his head from his armored body. As the helmeted head of Vader rolled past Skywalker's feet, the mask blew apart revealing Luke's own face staring back at him.
Another notable test was held at the Temple on Coruscant; granted the ancient edifice was in ruins and the Jedi Trials Chamber inaccessible. The Sith assassin known as Starkiller once again had infiltrated the Temple and headed straight for the Holocron Chamber within the Tower of First Knowledge. After opening a Holocron of his father, Kento Marek, the assassin fell into a trance and envisioned dueling a pure dark side version of his self. Turning his back on Darth Vader and the dark side so as not to wind up as the shadow figure he had dueled, Starkiller left the Temple for the final time.

The Trial of Spirit is a test of a Jedi's ability to face their inner demons.
To pass this test, the Padawan enters a meditative state while in the presence of a Jedi Master. While in the trance, they face their inner demons, fears, and the darkness within. The Jedi Council does not determine what is pass or fail for this test.