The Creeper

	It acts like a parasite, but it spreads like a virus. I don't claim to know how it works, I just know that it does.
— Dr. Morris

Endoflorescens terribilis, also known as the The Creeper, is a fictional virus that plays a major role in the story of Advance Wars: Days of Ruin. It has very few recognizable symptoms at first, but is notorious for the parasitic plants that emerge from the bodies of its victims as the infection progresses.

History

Creation and the Meteors

The Creeper was invented as a bioweapon by Caulder; it was devastating and had nearly no symptoms until the blossoming at one's death, but he rejected it as a failure because its inherent photophobia made it unable to survive in sunlight. However, once the meteors struck, the entire planet was covered in dust, preventing the sun's rays from striking the surface and creating an ideal ecosystem for it to live in.

Days of Ruin

The virus is first heard of when it is described by Dr. Morris once the 12th Battalion encounters a field full of the flowers; he says that the virus had not yet infected anyone over the age of twenty, for reasons unknown. Soon afterward, Isabella contracts the disease and is considered incurable until she makes a miraculous recovery at the shelter. It then fades out until a mysterious mutiny occurs within the ranks of the New Rubinelle Army just as Greyfield was about to crush his enemies. Several captured soldiers reveal that the virus had began spreading like wildfire throughout the ranks, making it clear that the virus had adapted to infect anybody regardless of age. Upon being scanned, over half of the battalion is infected. Morris is able to develop a vaccine for the virus, and is making progress towards a cure, when he discovers that all nearby medical facilities had been looted by Greyfield so he wouldn't become infected. The 12th Battalion manages to defeat the NRA and take the vaccine, distributing it to all the uninfected, and Morris manages to cure all the others.

Symptoms

	He had roots and leaves growing under his skin... In his ears... In his eyes...
— Lin

It is clear that the virus had very few noticeable symptoms. Although Will and Brenner were able to tell when Isabella was infected, the virus soon lost many of its traits. After the discovery of the virus' infection of grown soldiers, its only visible symptom before death is a black diamond mark that appears on the skin shortly before the blossoming.