- "We know only two things: we're running out of time, and you can never trust a Virus." -Dot Matrix
A Virus is a computer program that can infect a computer without permission or knowledge of the User. They are one of several types of formats found in Cyber Space. Viruses are generally very aggressive and destructive, thinking only of themselves, and usually possess powers and physical strength beyond those of most sprites or binomes.
Viruses seem to have a rather eccentric obsession with acting like royalty. Several like having a throne room, with a throne to sit in, and like grandiose buildings to live in, particularly towers. Megabyte had the tower Silicon Tor, Hexadecimal has a tower named her Lair, and Daemon had the tower of the Principal Office in the Super Computer.
Many viruses have a growth on their head similar in look to a Crown. This enhances their wish to be treated like royalty. Some even give themselves titles, such as the Queen of Chaos, or Destroyer of Systems.
Viruses and Code Masters have a rather unpleasant history. It is unknown what has taken place between the two races, but it is possible that Code Masters are often hired to delete viruses. Due to the amazing power some viruses possess, many Code Masters, although powerful, may have been deleted in the process. (High Code)
There are several types of viruses. Megabyte is a Control virus, programmed to take control of people and systems. Hexadecimal is a Chaos virus, programmed to cause destruction and chaos to any person or system she encounters. Gigabyte was a Class-5 energy-absorbing virus, programmed to drain energy from any person or place and then destroy it. Daemon was a Cron virus, programmed to infect the entire Net and then order it to self-destruct. Megabyte was later reprogrammed to be a Trojan Horse virus, programmed to copy other programs' appearances and cause destruction.
Gigabyte is the only virus ever given a classification number. No other viruses were identified by a number, so it is uncertain how the other viruses are in comparison. (Gigabyte)
Viruses also come in a more powerful variety called a Supervirus. Daemon and Gigabyte were super viruses. They are considered a direct threat to the entire Net, not just single systems, and are to be deleted immediately no matter what the cost. Some consider Hexadecimal to be a Super virus because of her incredible viral powers and transfinite power reserves.
A fourth variety of virus is the Viral Bug. They are small mindless bugs that begin spreading their infection as soon as they activate. The only one encountered was the Medusa Bug. It was created by Hexadecimal and activated by Megabyte. It turned him and the rest of Mainframe to stone within the computer equivalent of a few hours. It was incredibly powerful, and difficult to identify or diagnose a cure for; an amplified Viral Erase Program only worked for a moment before the affected area went back to being infected. Simply anything that touches them or things infected by them will be infected. Even Phong, who cannot be infected by a virus like Megabyte, was infected by the viral bug. The only known immunity to a viral bug is guardian code. The only thing that could counteract the Medusa was its creator, Hexadecimal. (The Medusa Bug)
The last type of virus is a Benign Virus. A prankster virus that does not cause any harm to a system or its people. They are powerful data-beings that try to directly annoy and troll the User instead. Benign Viruses would, for example, do things such as randomly display messages via Vidwindows. Fortunately, most viruses on the Net are benign. Guardians however, treat them no differently from other dangerous malware and attempt to delete on-sight, a practice Bob vehemently opposes. The only Benign Virus seen in the series to date, was the chaos virus Hexadecimal after she was de-powered by the Nulls (Cross Nodes). Bob had first hoped the virus Gigabyte was such a program, but was sorely mistaken. (Gigabyte)
Viruses do not reproduce in the traditional method that sprites and binomes do. Viruses can receive upgrades or downgrades from the User that created them. Each time this happens, the new virus takes a new name, and has very little memory of their previous form. The old virus is considered the parent of the new virus, and the new one is the offspring, or next generation. The best example is the virus Killabyte is the father of Gigabyte, and he is the father of Megabyte and Hexadecimal. The final two are considered siblings since they formed at the same time from the same virus.
Many viruses have the enhanced strength, speed, reflexes, and durability to handle any type of punishment inflicted on them to go along with their infecting abilities. Hexadecimal and Megabyte both have sharp claws on their fingertips that can shred through anything within the digital world. Though unknown with the rest of the viruses, Megabyte has a regenerative healing factor within him, which allows him to survive many of the injuries and attacks given to him with no lasting effects. Sometimes they could detach or shapeshifting any part of their bodies, such as the case with Hexadecimal's masks or Megabyte detaching himself to suit his throne.
There are several devices and weapons that have been invented, both by the User and system inhabitants, to erase viruses. A primitive device called a Viral Erase Command is an old version of this type of technology. It is not used much anymore, but one did still exist in the Mainframe Armory. Deletion Chambers can also be used, if the virus can be captured and place inside the device. The Gateway Command was modified to erase Daemon by fragmenting her. Some viruses are too powerful to be destroyed by guns or knives, conventional weapons are useless against them.
There are some viruses that have been encountered whose function and sometimes names were not given.