Rei Ayanami
, is the Prototype, the first successful Evangelion, and is piloted by the First Child, Rei Ayanami. The head design is similar to that of the previous failed attempts, with a single round optic in the center. Unit 00 is the only one of the original Evas that is never seen without its armor with the exception of Unit-03 (Unit 02 was revealed in "End of Evangelion", and Unit 01 on multiple occasions) or opening its mouth; thus the appearance of its organic body is unknown.