Thunder Sabre (雷光衝破突, Sandā Sāburu) is a technique utilised by Ranke by drawing energy from the Stone of Gelel.
Ranke collects a large amount of lightning energy converted from the Gelel source, in her body and in her hand, presses it together in a round ball, and then releases it at her opponent in the form of a punch, causing a huge explosion. It was powerful enough to punch through Gaara's Shield of Sand and send the young shinobi crashing through a wall.
Although the Japanese subtitle of this technique is written in kanji, it is pronounced in English, "Thunder Saber" (サンダーサーブル, Sandā Sāburu). The Japanese pronunciation of the kanji would be Raikō Shōhatotsu, which would literally translate to "Flash of Lightning Collision Break".