Azure Plasm, also known as Azure Plasma, is the name given to the unformed chaotic creatia in the realm of Coldharbour. Chaotic creatia takes a different but planar-appropriate form in every realm of Oblivion. In Coldharbour, a realm known for mimicking and stealing parts of Tamriel, it takes the form of ubiquitous pools of blue slime which functions similarly to water, and is even inhabitable for many aquatic creatures such as fish.  The Village of the Lost, a border realm of Coldharbour created during the Planemeld, was notably covered in a sea of the fluid while it formed.
When a Daedra native to Coldharbour is slain or banished, its morphotype, or vestige, is sent back there. Within Coldharbour are secret grottoes where the process of plasm-accretion can be witnessed. It is here the Azure Plasm drains from pools adjacent to the grottoes and slowly coalesces around a vestige to eventually reform the Daedra. It is usually a terrifying and lengthy process for the Daedra involved, although it can be prevented through resurrection with the use of Soul Magic. The process is identical for mortals whose soul is under the protection of a Daedric Prince, such as Soul Shriven; the Azure Plasm coalesces around a vestige and forms a corporeal body with the semblance of the shape it wore in life. Should this individual die, the nature of the vestige is such that their body simply reforms upon death and the cycle repeats itself.
A new realm being formed from Azure Plasma