The Orbs of Darkness were created by Julkolfyr upon the Codex of Creation, before the Shattering Disunity. These cosmic bodies wander the Universe and irreversibly consume everything that comes near and negate physics within their field of influence, making them supremely destructive. The Orbs appear perfectly black and spherical.
56 Orbs of Darkness exist throughout the entire universe, and no known way of creating or destroying them exists. They range in size from a planet's core to a nebula. A field of influence extends from their surface for a distance inversely proportionate to the Orb's size: the smallest have a field extending for a few hundred thousand miles, while the largest have a field extending for only a couple hundred miles. In practice, there is no way to reach the surface of an Orb, such that it's field of influence is virtually indistinguishable from the Orb itself.
The original design of the Orbs of Darkness was to utterly destroy any and all matter and energy which entered the Orb's field of influence, and to negate physics within that region. However, this original design was modified in the Codex by Vowzra, such that rather than destroying matter, it is fed through a one-way portal into the Gap.
Experiments by Teknall have indicated that the fringes of an Orb's field of influence do not have a sharp cut-off, but rather progressively suppress physics with increasing depth, nullifying gravity, progressively suppressing magic, and weakening electromagnetism (causing darkness). Before physics can be suppressed to the point of destroying matter, the Gap portal is reached. Within the Gap, the Orb of Darkness strongly repels everything nearby, preventing anything from exiting the Gap via the Orb.