The basic building blocks of Borg assimilation, these submicroscopic, self-replicating robots permeate the bloodstream and carry Borg technology throughout the body. Nanoprobes attack the victim on a cellular level, latching on to the blood cells and taking over their functions, rewriting their DNA almost instantaneously. The subject's skin turns gray within seconds, and develops a distinctive mottled pattern. This stage of assimilation leaves a subject passive and suggestible, paving the way for further alteration with cybernetic implants.