A nanite is a robot the size of a nanometer or smaller. In the popular Valiant series, Bloodshot has billions of these microscopic machines in his bloodstream. Biomolecular nanotech motors enhance strength, speed and reaction time beyond the limits of a normal human. Due to a nanites ability to create, manipulate and destroy matter on a subatomic level, the true limits of Nanites are unknown.
Nanites possess the ability to reconnect torn skin, arteries, muscle tissue and nerve fibers; rebuild bone; and repair and reconstruct damaged organs to allow for rapid and complete recovery from extreme traumatic injury. Nano-manipulation of physiological responses allows humans with nanites in their blood stream to survive extended exposure to hostile ond toxic environments, including extremes of heat and cold, high atmospheric pressure, low-oxygen environments and long-term kick of food and water.
Nanite implants expand the range of sensory function, extending hearing into the ultrasonic and sight into the infrared and ultraviolet ranges. The nanites' full control over cellular structures allows Bloodshot to shape-shift or "morph" for limited periods of time.
Although it is highly unlikely, hostile forces with their own nonotechnology could theoretically hack and reprogram the nanites. Some scientists fear that molecular self-assembly could allow nanites to replicate uncontrollably. The potential for nanites to self-replicate is also the basis for the apocalyptic "Grey Goo" theory. This is the idea that self-replicating nanites mass producing uncontrollably could form an ever-growing wave of "Grey Goo" that would devour all matter on Earth.