Indigenous to Stara Ziema where they are born in spawning pools by a Nxla queen, a variant of the typical Nxla that needs no host to survive. These nutrient rich pools incubate the small Nxla until they are able to be fused with a living organism. Their use in the Rephan Empire is as old as the empire itself and few if any seem certain whether the creatures existed prior or were the creation of Rephan mages.
Predominantly insect in appearance and nature, they have some biology that relates to other creatures like amphibians and crustaceans. A spinal column protected in an chitinous exoskeleton merges with a hand-like claw with many tendril that protrude from it like a jellyfish. The column is fused with the host's own in a very painful merging, the claw portion affixing to the base of the host's neck, and the tendrils attaching to places of nourishment and nerve fusing for the Nxla. If a Nxla is removed from it's host, it has an 80% change of dying. The host fairs even worse, and those who might survive often face paralysis, systems failures, and psychotic episodes.
Specially trained mages, aptly named Nxla Mages, handle these procedures as well as the taming and controlling of the wild Nxla behaviors to make them serve their purpose in the Imperial society. Among these purposes is to grant military teams a form of communication with commanders far away, much like having a radioman on a WWII battlefield. Another is a horrific means of empowering mages further than they are otherwise naturally capable, but its far too risky and the advantages too few to see this done commonly. The third is to create agents within other cultures, coaxing or extorting someone into fusing with a Nxla so that their lives and what they do and see can be transmitted back to the Nxla Mages and thus to Moloch himself.
Despite their use, Nxla are relatively rare as are their Mage counterparts, who account for perhaps less than 2% of mage in all of Stara-Ziema. These mages often study vaguely similar magical forms like shadow and alchemic schools to make themselves more useful than just pet wranglers and communication towers. They also seem to share a very introverted lifestyle, rarely even working with each other, let alone anyone else unless commands are given otherwise. Quiet, hermit-like lifestyles are quiet the norm and it's rumored than it has something to do with their contact (as part of their training) with Nxla Queens, whom generally only they have seen.
Hosts are 99% sentient beings and most of those are Furres as reptilian and avian species don't share the sort of temperatures and nutrients a Nxla needs to survive. When a Nxla completes a successful fusion with a host, there are several weeks of recovery usually taken so both can acclimate to each other. Afterword, the host will show no signs of change to their personality or physicality other than the visible spinal attachment attached above the flesh of the host's own spine and a wavered attention span as their mind is thinking for two. Psychological damage can be done however as the mental presence can create many different kinds of mental dysfunctions, but schizophrenia the largest potential. The user may find his magical or psionic abilities becoming slightly more powerful but harder to control, at least for a time. Non-formerly empowered hosts may feel heavier for a while but lighter as they get used to it all.
Nxla has been known to be quite the medical marvel as well as they encourage healing of the hosts body, even taking poor organs and helping them to function better by fighting off disease as well as wear and tear or deformity. This is often negated as a treatment however as the process would likely kill unhealthy hosts during fusion. But even healthy hosts will find themselves just as easily at the mercy of conditions like the flu.
Life Span: Undefined. They have a high mortality rate because of their host or poor spawning conditions, but some have lasted upwards of 200 years on multiple hosts. None have seemed to die of "old age".