Chi



Chi refers to metaphysical energy that flows throughout the body. In real life, chi is a Chinese concept prevalent in traditional philosophy, medicine, and martial arts. It is used in the Avatar universe as a concept that serves as the root of bending and an array of other skills.

History
During a healing session conducted by Yugoda, the elderly instructor demonstrated a technique of healing by guiding water through a network of chi paths carved into a life-size mannequin. An anxious General Fong made several attempts to induce the Avatar State in Aang when the team ventured to his base. One of his methods involved Aang drinking a chi-enhancing tea designed to increase the energy of a warrior ten-fold. This, however, only brought on a hyperactive state in the Avatar. During a duel in Omashu, Ty Lee first demonstrated the unique ability to block one's chi, thereby rendering one defenseless. By striking certain pressure points, she was able to strip Katara of her waterbending abilities temporarily.

Huu, a dweller of the Foggy Swamp, preached to Team Avatar how all living organisms were interconnected and shared the same roots. With this knowledge, Aang was able to tap into his chi and locate the currently lost Appa and Momo within the swamp. Guru Pathik demonstrated a similar ability to connect with his own chi paths and locate the Avatar in Ba Sing Se from his home at the Eastern Air Temple. Under Iroh's tutelage, Zuko was taught lightning redirection, a technique that enabled a firebender to absorb the lightning's immense energy within their body and release it in a more desirable direction. One crucial move in the redirection process is to guide the energy through the stomach, described by Iroh as one's "sea of chi". While practicing the motions for lightning redirection, Iroh asked whether the prince could feel his chi flowing throughout his body to which the latter replied yes.

Combustion Man, an assassin hired by Zuko to eliminate Aang, had the deadly ability to detonate explosions at will from a third eye tattooed on his forehead. Unfortunately, being struck in the third eye would temporarily result in his chi being disrupted and failure to trigger an effective explosion; this ultimately led to his demise at the Western Air Temple. While residing at the Black Cliffs, Katara attempted to calm an unsteady Aang by guiding him through exercise routines in a hot spring; while performing the series of stretches and movements, one was to be able to feel their chi paths flowing smoothly.

The anti-bending Equalist organization has demonstrated the ability to block one's chi. The Dragon Flats district, located in one of Republic City's residential areas, was one particular chi blocking training facility where non-benders were taught the method in secrecy. They have been seen immobilizing several victims, including Avatar Korra, with this technique.

Roots
There is a deep connection between chi and bending: seeming as if modern-day bending, in and of itself, is merely the ability to manipulate one's chi to the point where one can interact with and affect the environment. Due to chi, the four bending arts are truly one and the same.



Enlightened individuals, such as Guru Pathik and Huu, further explained the concept of chi as the life energy that dwells inside every living being connecting them to each other, their surroundings and the universe as a whole. Different parts of the human body contain concentrated clusters of chi, better known as chakras, or "pools of energy" as Pathik called them. When unlocked, these chakras are crucial for the Avatar to achieve his or her full potential, channeling his or her own energy as well as the energy from the universe.

Humans and higher animals have the potential to become deeply connected to one another, thus enabling Pathik, Huu, Aang, and potentially others to locate living beings out of sight and detect their thoughts and emotions by tapping into their chi.

Different types of benders, the Avatar and even non-benders, have shown skill in the art of chi manipulation, proving it to be a universal skill that can be learned by anyone.

Chi and the modern bending arts


Due to their heightened spirituality, all Air Nomads are born airbenders. The tattoos which they receive upon becoming airbending masters run along their chi paths. It is for this reason that Air Nomad Avatars' tattoos glow when under the influence of the Avatar State.

As Iroh explained, chi can be felt swirling around inside one's body, and the path can be changed to allow energy to flow in certain directions, which is the basic concept of lightning redirection, a move he invented by studying waterbenders. In actual waterbending, waterbenders directly use their own chi to mimic the moon's push and pull on the ocean tides. Combustion Man had the unique ability to gather chi from his stomach, the "sea of chi", and channel it to his forehead, creating localized explosions via a tattoo over his Light Chakra.

Chi blocking


Ty Lee, having an unparalleled knowledge of the human body's chi paths and their weak points, used chi blocking to a great extent in battle to either incapacitate, paralyze, and possibly even kill her opponents. She could even use this ability to disable another's ability to bend. Additionally, this art is utilized by members of an organization known as the Equalists, who employ this method as a means to counteract bending.

Healing
A select few waterbenders are born with the ability to heal themselves or another by using water to redirect the chi in a person's body, revitalizing healthy chi energy and speeding up their healing process. Though powerful, healing cannot cure the effects of chi blocking and other injuries where one's chi paths are blocked or disrupted like internal wounds and birth defects. Katara, perhaps the most powerful healer shown in the series besides Yugoda, who taught Katara the ability, was not able to counter Ty Lee's chi blocking on the fallen Terra Team soldiers.