According to Japanese legend, a ninja was a warrior specially trained in a variety of martial arts. The role of a ninja included assassination, spying, and investigation. Ninja’s were usually under order of a feudal Lord or guerilla warfare. In today’s culture ninjas are portrayed in non-factual ways for humor or entertainment. Some examples of ninja in works of fiction are Ask a Ninja, Ninja Warrior and the Teenage Mutant Ninja Turtles. Now there are costumes available if you want to dress as Donatello, Rafael, Michelangelo, and Leonardo from Teenage Mutant Ninja Turtles.
Perhaps you may want to dress as a traditional Ninja. Ninja outfits usually consist of two pieces, pants and a long sleeve robe that wraps around with a belt. To disguise themselves ninjas wear a fabric mask that covers everything but the eyes. Typically all pieces are the same color. You can even add a weapon such as sword for a skilled expert look.