Sometime during the course of Anakin Skywalker's Padawan training, a lightsaber battle unfolded within the hallowed halls of the Jedi Council Chamber when a formidable dark side entity manifested before him in a potent Force vision.
Following the Battle of Naboo, while training with Jedi Master Tera Sinube at the Jedi Temple located on Coruscant, the young Padawan Anakin Skywalker experienced the sensation of being choked by an unseen force, triggering his Force sense.
That evening, sensing a disturbance in the Force, Skywalker departed from his dormitory and proceeded to the Jedi Council Chamber, where a dark side entity materialized before him. Igniting his lightsaber, Skywalker engaged the entity in a lightsaber duel, questioning its intentions. The entity then proclaimed that he would succumb to the dark side of the Force.
In a foreshadowing of his future attack upon the Jedi Temple, a group of vulnerable younglings materialized within the Jedi Council Chamber. The entity asserted to Skywalker that he was powerless to save them, and that their destiny was already predetermined. The entity then assailed him with Force lightning. As his hope dwindled, Skywalker instinctively employed telepathy to reach out to Padmé Amidala, who perceived his desperate plea across the galaxy, on the planet Naboo. Concentrating on his close friend, Skywalker became infused with the power of the light side of the Force and vanquished the entity.
Following the event, Jedi Knight Obi-Wan Kenobi, alerted by Tiplee, discovered his apprentice within the Jedi Council Chamber. The weary Padawan was subsequently escorted to his quarters, where he drifted off to sleep. In the hallway, Grand Master Yoda conveyed to Kenobi that Skywalker had undergone a profound vision and that perhaps, in time, its meaning would become clear.