While they do seem to use their own designs, novel (and doujin) Nueroi seem also to take over and use Earth matererials and equipment. (Perhaps in a manner similar to the Boomers in Bubblegum Crisis.) Additionally, they also appear in greater numbers, and more often, than they do in the anime. In one chapter of the Suomus Misfits Squadron light novels, Tomoko Anabuki is part of a fight involving over sixty Neuroi. The only time there seemed to be that many Neuroi in the anime was in the second season episode where Hanna-Justina Marseille shows up.
