Originium is fictional material in the story and lore of Arknights. It is a black, translucent ore found in nature, containing vast amounts of energy and is associated with Disasters.
As Disasters plague the world, originium is discovered in its remnants in great quantities. As further research into harnessing it for energy furthers, technology progresses in such a way that originium use becomes an industry of its own. Rhine Lab is an example of an organization that focuses on researching originium and the technological uses that can arise from its utilization.
Exposure to originium may cause a disease called oripathy, or originium disease. No cure for oripathy has been found, and the disease has 100% mortality rate. Oripathy infection can be determined by detection of originium patches in or on the body of the infected. This patch tends to grow, and will consume the body entirely after death. The severity of the patches is then used to classify the severity of the infection, which is separated into infection stages I, II, and III.
Since the body will then contain a pile of originium after the death of the infected, they are generally feared by the society and are discriminated against all over the world in many forms. Rhodes Island seeks to solve these problems on a case-by-case basis with an end goal of providing care and home for the infected, while the Reunion Movement aims to break down the current system to pay against the discrimination they suffer and create a home of their own.
Infection by originium may grant the infected a way to utilize it to change reality to a certain extent. This is called originium arts, or more simply Arts, and is generally regarded as magic. Caster operators typically specialize in Arts.
However, developments in originium technology allows for non-infected to utilize Arts through artificial means, although the extent to which they use it depends on the arms they use. Therefore, operators who are not infected may still have a rank in Arts, if they master it well enough.