The N-4 Virus
Commonly called N4 or Nerotonin Type 4, the artificially engineered virus which caused most of the world's population to turn into zombie-like beings or even mutants has various effects of scientific and practical interest.
While there are no known remains of detailed plans about what Nerotonin 3 was exactly supposed to be capable of, nor are there any details of what exactly turned the prototypes of Nerotonin 3 into a virus totally unlike Nerotonin Type 2, various survivors have observed and learned from the hordes of infected over the years and noted a confirmed list of virus effects.