Genjutsu: Kurakugan

By establishing eye contact with an opponent, the user can induce a genjutsu that causes the target to believe that they are in a nightmare-like landscape, while constantly under attack by monstrous entities. The user is also able to infuse their chakra into the opponent's brain, causing the target to periodically see an illusion of the caster. This illusion is capable of psychologically torturing the target, playing off their fears and is capable of staying in the target's mind for decades, often driving to unfortunate victim insane. With another dōjutsu or a proper medical procedure, the infused chakra can be removed from the target. The overall strength and effectiveness of this technique depends on the user's creativity.