The Iroiit are a species of sapient metal-eating beings with a short stature. Native to Mata Nui, they formerly lived deep underground until miners in Onu-Koro made contact with them. They are rather reclusive and somewhat docile, and are rarely found in the company of their own species.
Iroiit share a similar body shape with Matoran, except they are slightly taller, and possess four arms. They do not wear Kanohi, for they had never came into contact with them until meeting the Onu-Matoran. They also have a set of teeth that is used to grind metals, for it is the main part of their diet.
One set of arms ends in simple hands, while the other set of arms end in claws, which they use to dig through dirt. They also have what can be described as fangs along with their teeth.
Matoran and Iroiit are biologically different, and are unable to breed together. Their diet is incredibly different as well, for an Iroiit does not require the normal foodstuffs Matoran need, only eating metals and other minerals and ores. They are also known to eat soil, where they get their liquids from.
Having spent most of their life digging tunnels deep underground without light, Iroiit have developed night vision, allowing them to see in even the darkest of places. They can eat metals rather easily due to their teeth and saliva, which can weaken metals. However, they are unable to use mask powers or elemental powers, but possess much greater stamina than most species, and have tough skin from all their years underground.
However, their night vision has the side-effect of making them less tolerant of sunlight.
Due to their lack of innate elemental powers, the Iroiit do not have any variations other than a gender divide and the colour of their armour, which varies between members.
Iroiit normally live by themselves, digging through dirt to find metals to eat. They only have family groups when young, setting out by themselves when they come of age. They also have no sense of right and wrong, nor do they know of evil and good, merely living and dying. Iroiit only settle down when they meet another of their species.
- Iroiit were first conceived after Hubert had a strange dream in which he was ordering pizza from a four-armed being with mouth weapons. This also later lead to Zaphos becoming a pizza delivery man in the RPG known as Techna.