Skirmish on Dathomir

In 2 BBY, a skirmish took place on the planet Dathomir between the Jedi rebel Ezra Bridger, the former Sith Maul, and the spirits of the Nightsisters who took possession of the rebels Kanan Jarrus and Sabine Wren. After a brief skirmish, Maul and Ezra escaped the cave but parted company shortly thereafter. Having completed a Magick ritual, Maul wanted to hunt down and kill his old enemy Jedi Master Obi-Wan Kenobi. However, Ezra wanted to save his friends. Returning to the cave, he freed Sabine and then convinced the spirits to release Maul in return for surrendering himself. However, Ezra then destroyed the Magick altar, destroying the power of the spirits.

Prelude
In 20 BBY, during the Clone Wars, the Separatist leader and Sith Lord Count Dooku sent a droid army led by General Grievous to wipe out the Nightsisters. Despite putting up a fierce fight, the Nightsisters with the exception of Mother Talzin and Asajj Ventress were wiped out. By 2 BBY, all that remained of the Nightsister lair were ruins and the remains of the fallen.

The former Sith apprentice Darth Maul was another survivor. Following the Clone Wars, he resurfaced on Malachor in 3 BBY where he sought to obtain a Sith holocron which contained the secret to destroying the Sith. There, he encountered the young rebel and Jedi apprentice Ezra Bridger, whom he encouraged to take an interest in the Dark side of the Force. Maul and Ezra were separated but Ezra took an interest in the Sith holocron.

A year later, Maul sought to combine the powers of the Sith holocron and Ezra's Jedi master Kanan Jarrus's holocron in order to find "hope." He kidnapped the crew of the Ghost and forced Ezra and Kanan to bring him the two holocrons in exchange for the safe return of their friends. Seeking to recruit Ezra as his apprentice, Maul convinced the boy to help him combine the two holocrons. While Maul saw glimpses of an old enemy and Ezra witnessed a world with twin suns, Maul's vision was incomplete because Kanan convinced Ezra to close his eyes.

Stalking Ezra
Despite his escape, Maul was unable to access the knowledge in the holocrons since they had been destroyed by an explosion. Due to the incomplete holocron connection, Maul and Ezra gained access to each others' knowledge and secrets. Discovering the location of the Phoenix Squadron's Chopper Base on the planet Atollon, Maul used his Dark Side powers and knowledge of Nighsister Magick to torment Ezra. He succeeded in terrorizing and unsettling the young Jedi apprentice. In the meantime, Maul gathered various artefacts from his past in a cave near the ruined Nightsister lair including the Darksaber to aid with a Magick ritual that would combine his and Ezra's minds.

After sufficiently unhinging Ezra's mind and confidence, Maul traveled to Atollon where he stalked the young Jedi. Ezra and Kanan communed with an ancient Force wielder known as the Bendu. Bendu identified Ezra's visions of Maul from a connection that had been created when the two combined the Jedi and Sith holocrons. Despite the Bendu's warnings not to turn, Kanan and Ezra turned to find Maul standing on top of a hill behind them.

Following a tense exchange, Maul managed to convince Ezra to come with him and complete the ritual by threatening to activate a homing beacon that would alert the Empire to the rebel base on Atollon. Kanan allowed Ezra to leave but attached a tracker to his wrist comm which allowed him and the Mandalorian weapons expert Sabine Wren to track down Maul and Ezra to the Nightsister lair on Dathomir.

Dark ritual
In order to join their minds, Maul and Ezra drank a potion brewed from Magick water. This caused their eyes to turn green and shoot beams of light which formed a cloud. Unknown to Ezra, this ritual involved summoning the spirits of fallen Nightsisters and Maul had sealed a secret pact to trade their flesh and blood. As a result of the ritual, Maul and Ezra learnt that the Jedi Master Obi-Wan Kenobi was hiding on a planet with twin suns and that he held the key to destroying the Sith. After the ritual, the cave turned dark and the altar began to radiate with the spirits of two Nightsisters, who demanded their flesh and blood as payment.

Before Ezra and Maul could leave, Kanan and Sabine arrived. Despite Ezra's warnings for them to stay back, the two opened fire on the apparitions. The Nightsister spirits took possession of Kanan and Sabine's bodies and used them to attack Maul and Ezra. Following a brief skirmish with lightsabers and blasters, Maul and Ezra managed to escape the cave. Since the Magick water was the source of their power, the spirits were unable to leave the cave. Maul tried to convince Ezra to come with him and become his apprentice. He also intended to seek out Kenobi.

However, Ezra refused to abandon his friends to the Nightsisters. Maul regarded Ezra as a "disappointment" but did not harm him and left on his ship Nightbrother. Ezra returned to the cave and confronted the spirit possessed Sabine. Following a struggle, he managed to push her out of the cave and exorcise the spirit from her. Ezra then returned and convinced the spirit possessing Kanan to leave his friend's body in return for offering up his own. The spirit accepted Ezra's offer on the condition that he defeat Kanan's body in a fight.

Ezra accepted the spirit's offer and fought with the possessed Kanan. After besting Kanan, the spirit left Kanan's body and attempted to enter Ezra's body. However, Ezra used his green lightsaber and the Darksaber to destroy the altar. This destroyed the Nightsister spirits' source of power.

Aftermath
After defeating the Nightsister spirits, Ezra briefed Kanan and Sabine about the information he and Maul had learned. He revealed that Master Kenobi held the key to destroying the Sith and that Maul was after Kenobi. Ezra, Kanan, and Sabine vowed to find Kenobi before Maul did in order to stop him from taking away their chance to destroy the Sith. In addition, Sabine took possession of the Darksaber, an ancient Mandalorian weapon and symbol of leadership.

Behind the scenes
The Skirmish on Dathomir serves as the climax of the Star Wars Rebels episode "Visions and Voices", which premiered on Disney XD on December 10, 2016. It recycled elements from the animated television series Star Wars: The Clone Wars including the Nightsisters, Nightsister lair, and Magick.