Kinjutsu

Kinjutsu
Kinjutsu are techniques that have been banned from being taught or used. This ban could have been put in place for any number of reasons, but kinjutsu can generally be put in one of three categories: Despite being banned, the mere use of these techniques generally does not carry any legal consequences in respects to the village they're used in, except those brought on by the techniques themselves. However, their use is heavily frowned upon, especially those techniques that violate nature. On the other hand, researching on and creating kinjutsu are punishable, as Stan Uzumaki was forced to flee Noharagakure after being caught doing forbidden Uzumaki jutsu, while Stephanie Oshino was classified as "International Criminal" once people found out she used the Ara Ara technique.
 * 1) Techniques that cause harm to the user themselves, such as the Wind Release: The Great Twister, which the mere use of is both highly useful as well as detrimental to the user. Although, with training, a user can overcome this weakness by compensating for it, enabling them to use the technique without any consequences, such as Stan using the Shinigami Realm jutsu to avoid damaging himself with the Great Twister. However, there are some that cannot avoid self-harm/sacrifice, such as The Reaper Death Seal or the Lightning Release: Flaming Thunder Shinigami.
 * 2) Techniques that violate the laws of nature, such as Lightning Release: Thunderclap and Flash, both the Shinigami Realm and Earth Realm, and the Summoning: Impure World Reincarnation, which reincarnates the dead with a human sacrifice.
 * 3) Certain techniques that are known to cause massive collateral damage, such as the total destruction of a village and end with the death of everyone in it, thus the great moral ramifications of its potential lead many to labeling it as a forbidden technique, such as the Tairyou Hakai which appeared to annihilate all of The Hidden Clay Village on a molecular level.
 * 4) Techniques that can manipulate the intellect of a person(s) and damage them psychologically. A very good example is Ara Ara, used by Kanaya Uchiha, Jett Uchiha, and Stephanie Oshino. This jutsu is able to manipulate the minds of any person with sexual desire, no matter how intelligent they are. This jutsu can also leave a handful of mental problems once released, ranging from Clinical Depression, to Schizophrenia.

Ninjutsu
Reaper Death Seal

Afterglow

Beheading Prison Chop

Shinigami Realm

Earth Realm

Summoning: Impure World Reincarnation

Lightning Release: Flaming Thunder Shinigami

Tairyou Hakai

Lightning Release: Thunderclap and Flash

Wind Release: The Great Twister

Twin Snakes Mutual Death technique

Curse Mandala

Creation Rebirth

Strength of a Hundred Seal

Mud Golem

Phantom Dragons Nine Consuming Seal

Ephemoral

Fury

Black Shadow Dismantilation

Genjutsu
Ara Ara

Kotoamatsukami

Izanagi

Izanami

Taijutsu
Eight gates technique

Crane wing formation

Daytime tiger

Evening Elephant

morning peacock

night guy

little toe attack

front lotus

One Thousand Years of Death