Thunder Shock Surprise

The Thunder Shock Surprise fires a concentrated lightning blast from both hands that traps the opponent in an electric field. According to Yamcha, the technique converts all the energy in the user's body into 20,000 volts of electricity. It is extremely lethal and virtually inescapable under normal circumstances. Master Roshi invented it but considers it so dangerous that he avoids using it whenever possible. Before his fight with Goku at the 21st World Martial Arts Tournament, Roshi had only ever needed to use it once before, during a sparring match with Grandpa Gohan.

Disguised as Jackie Chun at the 21st World Martial Arts Tournament, Master Roshi deploys the Thunder Shock Surprise against Goku as an absolute last resort. The electric field engulfs Goku and appears to have him completely restrained. But Goku spots the full moon, transforms into a Great Ape, and breaks free through sheer physical expansion. Roshi is forced to destroy the moon with a Kamehameha to revert Goku back to normal, making the Thunder Shock Surprise a failure in practice despite working exactly as intended.

Tournament of Power

In Dragon Ball Super, Master Roshi uses the technique during the Tournament of Power against Za Priccio, successfully trapping the Universe 4 warrior while Tien finishes him off with a Neo Tri-Beam. The technique also appears when a possessed Roshi, his power amplified by witchcraft, uses it to defeat Tien Shinhan while in Max Power form.

The Thunder Shock Surprise is one of the oldest techniques in the franchise both in-universe and in publication history. It predates virtually every other named technique except the Kamehameha and a handful of others. Piccolo later uses a very similar electrical attack against Great Ape Gohan during his early training, suggesting the technique or something closely related to it has spread through the martial arts community over the centuries. Its rarity makes each appearance feel significant, a reminder that Roshi's arsenal extends far beyond the Kamehameha.