The Dodon Ray (Dodonpa, Boom Wave) is a special attack used by Mercenary Tao and the members of the Crane School. It is never made clear whether Tao or his brother, Master Shen, invented the technique, but it is used by both. Unlike most other energy attacks, it seems to be something of a superheated beam, shown by one person in the Tien Shinhan Saga of Dragon Ball who was covered in bandages because of burns caused by the attack. It is definitely more powerful than an average Kamehameha, but unlike the Kamehameha, it doesn't seem to require much charging, but will definitely be much more powerful when doing so. Also unlike the Kamehameha, which relies more on brute force to blast an enemy away, the Dodon Ray is more concentrated in piercing through a specific point on the body.
However, there are much more powerful adaptations of the attack that exist. One of them is known as the Super Dodon Blast, which is only seen in use by Chiaotzu. This stronger version of the Dodon Ray requires the user to charge up as much power as possible and then fire it at the opponent, rather than shoot multiple, weaker Dodon Rays. It also creates a much bigger explosion upon impact. Chiaotzu uses this in his match against Krillin after Master Shen orders him to kill Krillin during their match.
The strongest adaption of the Dodon Ray is called the Super Dodon Ray, which is used by Cyborg Tao in the Dragon Ball Z and the Budokai Tenkaichi video game series, where he in his cyborg state removes one of his metal hands to fire one fueled by both his mechanical and organic components, which lands a heavy amount of damage. Tien, however, dispersed it in mid-air with a simple kiai when Tao launched it after cutting Tien's chest with a concealed knife.In the Dragon Ball Z: Budokai Tenkaichi video game series, Mercenary Tao's version of the Dodon Ray is called the original Dodon Ray.es:Dodonpa