Thread

The Thread are an intelligent species of creature native to the dimension of Reeval.

Background
The Thread exists as a densely interwoven mass of living tendrils that slowly writhe like elongated, milk-white worms. On in sum does the Thread possess some form of intelligence, while individual strands will have as much cognizance as lone, hive insects. Amid the larger Body the Thread cogitates as one massive, albeit very slow, intelligence. When a single entity, the Thread have many abilities that easily surpass understanding, even the ability to peer into alternate dimensions. But along the void interfaces of Reeval, the Tread can actually pinch off tiny sections of its form into minuscule sub-units in order to accomplish any specific tasks. These sub-units are seen as akin to individuals, tough no completely.

It's not very possible for a human being to understand the Thread, but it's easy to see what it can achieve, and can't achieve; the Thread possesses an amazingly vast intelligence yet at the same time lacking fundamental self-awareness. Like a great wind rushing over obstacles and around barriers without consciously choosing the many paths it must take in order to do so, the Thread continually cogitate, experiment, and expand their knowledge into difficult and challenging areas.

If the Thread lack self-awareness, they at least make up for by having an instinct for recognizing their lack (if it is is indeed a lack). Something about the self-directed nature of humans and other similar creatures in parallel dimensions draws the attention of the Thread so much that they've learned how to pierce the dimensional divide and extend exploratory probes into the strange (at least to them) dimensions of emptiness, individuality, and desire. After discovering these alternate planes of existence, the Thread then started to experiment wit creating empty spaces themselves - the voids, from within the Body.

The Thread possess an advanced technology based on biomodification and chemistry, allowing them to grow whatever they need, up to and including Nibovian automatons that can mimic the shape and - to some extent even - the minds of humans and other creatures of particular interest found within alternate dimensions. By growing segments of themselves in certain ways and in certain conformations, the Thread can create vast engines capable of launching the Nibovian lures into the dimensions they can see all around them, and use said Nibovians like remote manipulator arms extended into some deadly environment.

Thread Walkers
The Thread, insofar as they sometimes act as a single entity and other times as a series of individual subdivisions, don't have any leaders. Despite this, however, some Thread sub-units found within the Braid and few other voids learn about humans by creating puppets from smaller bits of themselves, and sculpting them into human-shaped bodies covered with cast-off skin segments harvested from humans, and further disguised with garments, gloves, hoods, and masks. These Thread "walkers" will sometimes take on the semblance of individuality. The faux-individuality will occasionally extend into goal formation that can differ from the Thread overall. Usually, such walkers are absorbed back into the Body well before true individuality can take from within them. Those that persist so long tat individuality actually precipitates tend to be found dried up and dead, as if self-awareness itself is antithetical to the Thread.

Because the Thread are so completely alien, they're unlikely to recognize dimension walkers exploring their realm instantly, perhaps assuming them to be instead another Thread walker. However, if the Tread of the Body does become aware that experimental subjects are loose within Reeval, then all of the Thread will slowly become aware. Alternatively, what an individual Thread walker learns won't be immediately transmitted to the Body, though it might soon after the walker in question is allowed to meld back into the greater mass of tendrils.