|"This is water from the Spirit Oasis at the North Pole. It has special properties, so I've been saving it for something important."|
|— Katara to Zuko.|
Spirit water is water imbued with spiritual energy, providing it with special healing properties. It is often taken from sources where spiritual energy is considered to be particularly strong. Notably, a vial filled with this water was used by Katara to revive Avatar Aang after the battle in the Crystal Catacombs.
Prior to becoming the Avatar, Wan was taken to a Spirit Oasis in the Spirit Wilds by the aye-aye spirit, the oasis' guardian, in order to tend to his injuries. After inquiring as to what the water contained that allowed him to recover so quickly, the spirit revealed to Wan that water from the oasis had special properties that aided in healing.
In 84 AG, Princess Yue was placed in the Northern Water Tribe's Spirit Oasis in a final attempt to heal her from a severe birth complication, as it was known that the water had special properties. Tui, the Moon Spirit who resided at the oasis, provided Yue with some of her own life energy, which the princess eventually returned in 100 AG after Tui's mortal form was killed during the Siege of the North.
Several weeks after the siege, Master Pakku provided Katara with an amulet filled with spirit water as a parting gift before Team Avatar set course for the Earth Kingdom and told her that the water, having been taken from the Spirit Oasis, possessed special healing properties.
While imprisoned with Prince Zuko in the Crystal Catacombs of Old Ba Sing Se, Katara was prepared to use the spirit water to heal Zuko's scar, but was interrupted by Aang and Iroh's arrival before she could attempt the process. During the ensuing battle, Aang was struck by a lightning bolt from Azula while he was in the Avatar State, killing him. In an attempt to revive him, Katara used the spirit water to heal Aang's wound, successfully bringing the Avatar back to life.
After Zuko joined the group to become Aang's firebending instructor, Aang attempted to dismiss the firebender's concerns of the consequences involved in failing to properly redirect lightning by ensuring that Katara could use the spirit water to revive him. However, Katara revealed that she had run out of the water, as she had used her entire supply in healing Aang after the battle in Ba Sing Se.
In 171 AG, an elderly shaman concluded that the cause of Korra's memory loss was due to a dark spirit who had attacked her and infected the Avatar Spirit. In an attempt to cleanse her body and aid her in reconnecting with her Avatar Spirit, the shaman ordered the members of the Bhanti Tribe to submerge Korra in a subterranean pool of spirit water in the Bhanti Village Temple.
Spirit water is considerably more potent than regular water, possessing special properties that aid in both physical regeneration and spiritual cleansing.
On a physical level, spirit water can heal minor injuries almost instantaneously, as the wounds and bruises which Wan had sustained following an altercation with hunters in the Spirit Wilds disappeared quickly after he was placed in the waters of the Spirit Oasis. Furthermore, spirit water can be used to heal fatal injuries sustained by individuals, such as injuries resulting from lightning attacks. Although it was never attempted, Katara also believed that spirit water was capable of healing physical injuries and disfigurations far past the capacity of normal healing, including scars.
The water can also aid in spiritual healing, as it successfully cleansed Korra's spirit of the infection from a dark being. It also allowed the young Avatar to connect with several of her past lives to the point where she was able to look deep into herself and connect with her first lifetime and examine the origins of the Avatar Spirit. Despite this, spirit water also has its restrictions. Particularly, although spirit water was able to revive a mortally wounded Aang, it was not able to open chakras that were blocked as a result of the attack, or restore Aang's connection to the Avatar Spirit.
Bhanti Village Temple
- Main article: Bhanti Village Temple
Located underneath the Bhanti Village Temple in the Fire Nation is a subterranean pool used by the shaman and the Bhanti Tribe for healing purposes, due to the high potency and regenerative capabilities of its waters.
The pool is an effective medium for facilitating spiritual healing, and allows for effective cleansing to purge the body of any unwelcomed intrusions, particularly in the form of spirit infections. The waters also allowed Avatar Korra to connect with and seek the counsel of her past lives.
North Pole Spirit Oasis
- Main article: Spirit Oasis
The Spirit Oasis in the Northern Water Tribe is a verdant and lush garden located in a cave behind the Northern Water Tribe Royal Palace. It is a place where the Spirit World overlaps with the mortal world, and serves as home to the mortal forms of Tui and La. The waters of the oasis also have unique healing properties.
Spirit Wilds Spirit Oasis
- Main article: Spirit Oasis
The Spirit Oasis in the Spirit Wilds was a small islet near a lion turtle who bestowed firebending. It was guarded by the aye-aye spirit, who only permitted spirits to enter the oasis prior to meeting Wan. The Spirit Oasis had waters with replenishing properties along with fruit-bearing trees.
- Main article: Spirit World
Bodies of water located in the Spirit World possess strong spiritual energy, making them highly desirable healing mediums given their potent regenerative capabilities. A stream near the Tree of Time was used to heal Korra, Bolin, and Mako at the same time during Harmonic Convergence. Although it had been inaccessible for over ten thousand years due to Avatar Wan's closing of the spirit portals, the stream was used extensively for both combative and healing purposes following the reopening of the portals by Avatar Korra in 171 AG.
- Three Avatars are known to have been healed using spirit water: Wan's injuries were healed in the Spirit Oasis located in the Spirit Wilds, though this occurred before he actually became the Avatar; Avatar Aang was revived using water from the North Pole Spirit Oasis, and Avatar Korra twice, first when her spirit was cleansed using spirit water from the pool in the Bhanti Village Temple and again when Kya used water found in the Spirit World to wake her up.
- When spirit water was first used by Katara to heal Aang, the water was used up. This was not observed in any other instance of healing which used spirit water.
- Spirit water has been used for physical healing without employing waterbending on at least one occasion; spiritual cleansing has only been displayed without the use of waterbending.