Z-COVID is a synthetic Imperial bioweapon made from the previous Z-29 virus. It briefly appears in the True Timeline following Operation: Final Strike, but mainly attacks a universe dubbed the Corona Timeline. It is able to create Zombies to increase the amount of people it infects, and attacks through acid and infectious materials.
Z-COVID was an experimental Imperial bioweapon meant to succeed Z-29, but was never released due to the fall of the Intergalactic Empire. However, the Imperial fleet led by Lord-Admiral Trenns Valarom survived and took control of the Interstellar Expanse, and used its resources to finish work on the virus. The Viewer, in control of Valarom, hid more pieces of his essence along the virus as a second contingency, and after his presumed destruction on Crassin Prime, took the virus and released it on a planet known as Dakk 3. Although the virus was fought off, a major amount of Z-COVID fled through a portal opened by The Viewer into an alternate universe, and nearly overran that universe's version of Earth.
Z-COVID often takes the form of purple, red, or grey gelatinous biomass. A large amount of such biomass can form into spherical structures with knobs resembling a WW2 sea mine. These structures, known as virus orbs, can open up to reveal teeth-like interior structures, and can then spew acid and infectious materials. However, they can also form into humanoid shapes of varying builds and sizes, even resembling uninfected humans.