Blood bending

Psychic bloodbending

A restrained Yakone effortlessly bloodbending Chief Toph Beifong.

Psychic bloodbending is the ability to use bloodbending without the aid of motion and movement of the hands or feet. Yakone first demonstrated this ability when he used bloodbending to control an entire courtroom while his hands were still bound by cuffs. He passed on the knowledge of this technique to his sons, Noatak and Tarrlok. However, only Noatak mastered the ability, doing so at the age of fourteen and able to control an entire pack of wild animals at once.

Bending severing 

Lightning Bolt Zolt losing his bending.

Bloodbending can be used to completely cut off a bender from his or her bending abilities. This technique has only been demonstrated by Amon and requires direct physical contact between the user's hand and the victim's forehead. The effects of this technique are long-standing, and, unlike chi blocking, it cannot be easily undone. According to Katara, the technique "severs" an individual from his or her bending, making it impervious to all methods of healing. Even so, only active chi pathways can be severed; Korra was able to use airbending because it was still dormant when her other bending abilities were removed. However, the severed bending can be restored through the use of energybending, as shown by Aang and Korra.<sup>[6]

Bloodbending is the only known way besides energybending to strip a person of their bending indefinitely. 

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