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The Kiko-ho (気功砲, Kikō-hō; FUNimation "Tri-Beam"; Literally meaning "Spirit Work Cannon") is a life-risking offensive technique used by Tenshinhan and taught by the Crane Hermit. Tenshinhan first uses this attack during the 22nd World Martial Arts Tournament against Son Goku, and used it at Kami's Lookout against Yamucha. This technique is performed by gathering energy, forming a triangle with the hand by keeping the fingers on each hand together, overlapping the index finger on the one hand with the pinky of the other hand, and overlaping the thumbs. The object being focused on gets zoomed in on and visualized inside that triangle, then the user (namely Tenshinhan) shouts, "Tri-Beam, ha!" while releasing the large yellow beam from the hands. He also has the ability to fire it with one hand as seen when he fires the Spirit Tri-Beam at Nappa after he loses his arm.
In addition to being able to kill the target, this attack can easily kill the user, as it drains their life energy. Interestingly, this technique leaves a square hole in the ground, instead of a triangle. After training with Roshi, Karin, Kami, and later North Kaio, Tenshinhan perfects the attack as the Neo Tri-Beam, which is essentially an "upgraded" form of the attack that allows him to control and enhance how much energy he puts behind it, inflicting even greater damage.
The attack formation itself places the hands in a seemingly awkward position - and it appears that later in the series, the finger tips are touching, and the thumbs are the only things that overlap.
The attack is extremely powerful. Tenshinhan once used it against Semi-Perfect Cell, and despite the massive gap between Cell and Tenshinhan's powers, Cell was unable to break through the repeated blasts, though they did not inflict any real damage to him. Tenshinhan eventually collapsed from using the technique too much, but was saved from Cell by Goku.
While Cell himself has not been seen using it (although it is likely he can, as he possesses Tenshinhan's DNA), during the Cell Games Saga, the Cell Juniors attacked Super Saiyan 2 Son Gohan with it, although to no avail.
Kikō (気功) is the Japanese translation of Qigong or Chi Kung, literally meaning "breath work" or "energy work", a traditional set of techniques for controlling breathing or circulating and cultivating chi (ki, energy) within the body which is tied to a number of Chinese martial arts and medicinal beliefs.
The Tri-Beam has two variations: