The Zenar Virus, or Z-2, is the virus that is responsible for ruining the World in just four short years, bringing the total population of sentient races to only 18% of what it was originally. It did not originate from some dark corner of the World unexplored, but from an experiment gone wrong. After the discovery of our World, a word used to describe everything that makes up everything around us, including dimensions, people began asking if they could travel to another World. It was thought to be impossible at first. Every attempt just opened up to a dimension or some alternate world that is not as advanced. However, one day Doctor Sigma Darvu opened up a portal to a whole new dimension, and that dimension being one not attached to our World. He got this from using pieces from our World's Hell.
The theory went that different Worlds' Hells are somehow connected and, seeing how the portal opened up to a subsection of a different Hell, it seemed to be correct. So, after much trial and error, a portal was opened up to Another World. It was open for two minutes before the first instance of Z-2 came through. At first, it was tiny snowflake-like black particles. Then, a black tentacle came out, latching itself to Doctor Amelia's face and transforming her into the first Zenar. It wasn't fast like it is now, and the portal closed right afterwards. However, by then it was too late and the tentacle was fully through, having gone into Amelia's skin. The people there watched as she was reverted back to a child, then suddenly transformed into the common Zenar. The people there did not attack first, but rather the Zenar did. Needless to say, no high tech weapon managed to do much to the Zenar. That added in with it infecting others, the Zenar Virus officially took a step into our World, one that would only continue to grow to an extent no one has ever seen before.
At first, Z-2 was thought to be a fungus for its hivemind-like intelligence, the spores it creates, and how it gathers in clumps. However, it soon became clear that it was, in fact, a virus that nearly acts, if not is, somehow sentient. Spread by spores or by the Zenars themselves, or defense structures build around Z-2 sites, even the bounds of space cannot affect this virus, with large colonies, or sites, being connected between whole planets and stars.
It is unclear what the Zenar Virus fully does to their host, but whatever it did, they made them a near impossible foe to beat. One single common Zenar, if pissed off enough, can punch a planet close to twice the size of earth into a dozen pieces, and chances are it can do much more than that. This is thanks to the red lightning-like energy that the Zenar Virus creates. However, seeing as Zenars always hold back what they are fully capable of doing, and how they can do one thing then, a couple of seconds later, fail to do it again, suggests that either there is a strain on the host or the virus is connected to the mind of its host. Zenars can be "killed" by regular weaponry, but only after a lot, and a Lot, of stress is done to it. Whether that be through firepower or something else. One must mentally drain, or really trick, the Zenar into thinking it is weak. However, any type of mental manipulation utterly fails and may result in all Zenars around targeting the source.
The most recent study of the Zenar Virus revealed two things. One is that Z-2 is a runoff strain, meaning it wasn't the original virus. The next is that the virus seems to need, or have a source. One site or Zenar to rule them all. If this thing, named Denvar, is destroyed, it is not known if another one will rise in its place or the virus will die out. However, whatever this Denvar is will definitely be well-protected, and can probably use the full extent of what a normal common Zenar can do. Whether it can be killed may be the least of our problems, as the consequences of trying to should be taken into account. After all, it seems the Denvar is something akin to a God in Zenar society, and they will most likely go to extreme lengths to protect this thing if it really is real.