Dirty Fireworks (汚い花火) is a technique used by Vegeta. With the enemy on the ground or in the air, Vegeta aims at them with his outstretched index and middle fingers held together and creates a huge explosion on the opponent, inflicting a great amount of damage.
Vegeta first uses this attack to kill a Saibaman for holding back during his battle against Tien Shinhan. Later, on Namek, Vegeta uses it to kill Cui while the latter is fleeing from him in the middle of their battle.
Frieza uses a similar attack to kill Krillin after nearly killing Piccolo with a Death Beam. However, this ends up being the tyrant's downfall, as this action pushes Goku over the edge, transforming him into a Super Saiyan for the first time.