Brave Cannon (ブレイブキャノン) is an energy sphere technique used by Trunks in Dragon Ball GT, and Tapion in the video games. First, the user puts his two arms on his right side and charges a large, powerful ball of ki. Then, he throws the ball at his opponent, causing an explosion which inflicts a large amount of damage.
Trunks first uses it on Planet Luud to destroy the tiles Mutchie is throwing at him and Goku. He later uses it to kill Mutchie while he is absorbing Goku's energy. It is very similar to the Finish Buster used by Future Trunks.