Kidoumaru is the spider-like member of the Sound Four; he possesses four extra arms, has the ability to make webs, and even possesses a third eye. Kidoumaru’s webbing is made of a special type of liquid that is created by infusing body liquid with chakra, making it as strong as steel. Kidoumaru can create a stronger, golden webbing called Spider Sticky Gold that hardens upon contact with oxygen to metal-like quality. Because of the solid nature of this webbing, Kidoumaru can shape it into armor or weapons to aid him in battle.

(Source: Wikipedia)