According to the special magazine Dragon Ball: Bouken Special, Ninja Murasaki's four brothers are named Kon, Aka, Nao, and Cha. Nao means "blue", Aka means "red", Kon means "navy blue", and "Cha" means "brown" in Japanese. Those colors mixed with each other gives purple, the meaning of "Murasaki" in Japanese.
The four were supposedly "clones" of the original Murasaki but, in reality, they are his identical brothers. They each wield a different weapon. They distract Goku while Murasaki escapes. Goku manages to defeat all of them with punches, kicks, and the last one with a Power Pole whack to the head.
Dr. Slump remake
Ninja Murasaki and his four brothers appear in the crossover episode "Gokuu-kun Arale no Gakkou de Dai Pinch!" of the 1997 Dr. Slump remake. When Goku arrives in Penguin Village with all the Dragon Balls in his knapsack, except one that Arale Norimaki had found, Murasaki and his brothers attempt to get them all from Goku but are defeated by Arale and Goku working together.
The five brothers
Main article: Ninja Murasaki The oldest of the brothers, and the one who confronts Goku on the Muscle Tower.
Kon (コン) is the 2nd oldest of the brothers. He is defeated by Goku in the Muscle Tower, as are the rest of his brothers. Kon usually wields a set of kunai knives.
Cha (チャ) is the 3rd oldest of the brothers. He is defeated by Goku, as are the rest of his brothers. Cha wields a British Webley Mk. IV revolver.
Aka (アカ) (not to be confused with the movie villain) is the 4th oldest of the brothers. He is defeated by Goku, as are the rest of his brothers. Aka wields a blowgun.
Nao (ナオ) is the youngest of the brothers. He is defeated by Goku, as are the rest of his brothers. Nao speaks in a notably different accent (a slight southern accent) to the other Murasaki brothers. He wields a kusarigama.
Video game appearances
The Murasaki Brothers appear as bosses in Dragon Ball: Advanced Adventure, Dragon Ball: Revenge of King Piccolo, and Dragon Ball: Origins 2. The Murasaki Brothers are also referenced in Dragon Ball Heroes, as part of a special mission where a team of five Murasakis has to be defeated.