When a Strong Order arises a Reality may be born. Realities are the most important manifestations because they are the vessels for all other higher order manifestations. Realities provide the structures and laws that allow the existence, growth and change of all other things. Without a reality there can be no existence as we know it.
A Reality is formed when multiple Streams of Essence converge and intersect at a point known as a Nexus. When a Reality is first formed it must attain stability. Nothing we know of can force a Nexus to become stable. It either remains or, in an instant, dissipates, descending back into chaos. Nexus are continually born and die, but every so often, one remains. Some survive for a day, some a year, some a millennium, other have persisted for eons or longer; eventually they will all perish.
Once a Reality becomes stable it is very difficult to effect permanent change in it without an equally permanent intervention in the Streams that give rise to the Reality. One way to think of a Reality is as an island of stability in an ocean of chaos.