Terrigen
Terrigen crystals are a mutagenic compound created by the Kree Empire. Terrigen (along with Antigen, Isogen, Exogen, and Amphogen) was originally created by experiments using Primagen, also known as Prima Materia, that sought to find a way for the Empire to produce their own primagen.
Although these experiments were unsuccessful, the created compounds did still have mutagenic properties which were later used during the early years of the Kree-Skrull War to create the inhumans, Moord, and related mutated species.
Properties
Material Characteristics
In its base state, terrigen forms medium sized crystals. These crystals are water soluble, and can be crushed to create particulate clouds.
Physical & Chemical Properties
In those with inhuman DNA (descendants of those subjected to genetic experimentation by Kree scientists) exposure to even trace amounts of terrigen triggers a mutation process known as terrigenesis. Trace exposure does not harm most humans, but direct or prolonged exposure to higher doses is almost always fatal.
Compounds
In order to prseserve limited supplies of terrigen, the Attilanians combined particulate of terrigen with chemicals designed to speed up and stabalise the mutation process to create a terrigen cloud.
Geology & Geography
Terrigen is not naturally occuring. A small number of crystals remained on earth after the Unspoken drove out the Kree, but the majority were taken to the Moon by the Attlianians.
Following the fall of Attilan, and the release of Afterlife's terrigen supplies into the ocean, the only terrigen crystals remaining are those in the inhuman settlement of Orollan.
In 2018, many member of the former Inhuman Royal Family left Earth on a mission to find a new source of terrigen. They were able to retrieve a supply of primagen from the World Farm, and this has replaced terrigen in Providincian culture.