Zero is a Ta-matoran, also called Orez in all other metru. He was turned into a Heartless by Alpha-0 when he was told that Po-metru was making better disks with better protodermis types. He is known for being the only matoran that knows why Alpha-1 is Mycomecaphobic, meaning he's afraid of ants. He has a pet Kraata and is the only scientist inside Ta-metru, due to the fact he goes to metru interested with science, and uses his other tiem for his job at the Forges.
Zero is seen in the background in most episodes that have Ta-metru. He is also a main charecter in twenty episodes of Silent hero and a Hero in the BK movie VEI 10. He is Volcanologist, Biologist, and a Toxicologist.