Umbra, shadow between the stars (A to Z Challenge, U)25 April, 2016
Beyond the space between the islands, between the stars is the darkest of shadow, known as the Umbra to those who study such things. But there are being that live (or at least exist) in this strange space, the darkness between, is the home to a host of strange beings, many inimical to life as it is known on the islands, though they rarely venture into the Sea of Stars unless summoned by the foolish
These sub-umbral creatures come in a bewildering and frightening range of sizes, shapes and geometries, in some cases their mere presence warps and damages what is around them, others come from space so far removed from the standard conceptions of being that even looking upon them risks one’s hold on reality. The danger of summoning such alien creatures is often lost on those who have access to the tools to do so, as often their is no indication beyond some flowery description (“The darkness without”, “the infinite shifting flower” and such) about what they are bringing into the world. Once brought here, they are extremely difficult to control, fortunately in some cases the world is as inimical to these bizarre being as they are to the world, which does not prevent them from causing a great deal of harm before they die. They that the summoner can control sometime pose an even greater threat as the summoner will probably with to bring more and eventually they will break free.
The sub-umbral beings can be classified into families of strangeness each with similar characteristics but each branch is radically different from the others making classification difficult even when reliable data can be gathered about the sub-umbrals.
One of the secret tasks of the Imperial Navy and other Imperial forces is to locate and root out infiltration of these sub-umbral beings, luckily such tasks are rare as they can be exceedingly dangerous and dragons in Imperial service are routinely called in to support the sealing of such threats.
Notes: For those that want Lovecraftian or Far Realm strangeness in their Sea of Stars campaign, this is where it comes from. Umrays are one of the least strange of the sub-umbrals being from near space.