The virus

The virus is a recurring theme and event throughout the three games: Menagerie I: Exoptable Money, Menagerie II: Presentable Liberty and Menagerie: Archive. It is a deadly virus which causes infected individuals to feel increasingly unwell, symptoms include extreme lack of adrenaline. The symptoms would surface after a varied period of time, it would be nearly immediate as shown on Harvey Keller, or probably delayed like on protagonist in Menagerie: Archive, who showed little sign of symptoms. According to Doctor Money, 98% of the population have been infected with the virus in the beginning of Menagerie II: Presentable Liberty.

The virus was distributed by Doctor Money to the citizens in the game, it is portrayed as extremely contagious, merely opening the letters of the a contaminated letter would cause infection. It is possible the virus is also contagious by other means in Presentable Liberty, considering Salvadore discovered whole villages being annihilated by the virus.

In Exoptable Money and Presentable Liberty, a large population was dead by it, while in Menagerie: Archive, the resistance stated all citizens with a rank 81 or lower, aka. the lowest class of the society are infected by the virus. It is probably all of the citizens with rank 81 or lower died by the infection in most ends of this game. While it is possible the virus may have a cure, referred as "antidote", this cure is known to have serious adverse effect as referred in Exoptable Money, causing failure of vital organs. In Menagerie: Archive, the resistance claimed the antidote did not work. This contradicts with Doctor Money claiming it was working,

If the information of other games are considered valid in Archive, it would mean the antidote did not work, and eventually Doctor Money had no way to disinfect himself after killing everyone else in the world, and died of it. This might also mean in Archive, the protagonist is doomed to die in all endings, including two endings in Archive in which the protagonist gave all the files to Doctor Money in day 8, and Doctor Money either gave him freedom or let him continue his work, which should result in the virus killing him afterwards, although unmentioned in any ending of the game.

In Exoptable Money, the virus was created as a means to stop the east and west war as mentioned by Doctor Money. It may have succeed since after the war, there were not enough people on either side to continue fighting, or it might not be administered in the war at all. Nevertheless citizens are recorded to be infected by the virus afterwards. Doctor Money also sent contaminated letters to his employees to infect them, in order to force them to work for more money. Also, in Menagerie: Archive he sent similar letters to kill off unemployed citizens.