Dregs, or anomalies, are masses of black, viscous, oily slime that litters the Ultravoid. They appear to be living organisms and appear to have a connection the Remnants. Dregs appear in the form of walls and barriers between different regions of the Ultravoid that has to be purged in order to open up traversal between them, as well as in the form of anomalies that need to be purged to gain the attention of the Remnants, or possilby wake them up. Dregs have large dark pink eyes with black pupils on them which are their weakest spot.
Barrier Dregs seem more simple with their one eye being their only weak spot, though it is always open so it is easy to hit and break. Breaking their eye will cause the barrier Dreg to dissovle into nothing. The Dreg anomalies seem to be more complex organisms, having nerve endings that need to be struck in a specific order and in a specific time for its eye to open so that it can be struck and gain the attention of the Remnant or wake it up - whichever thing is happening. Eiher way, clearing an anomaly will cause a region's Remnant to open one of their eye until all anomalies in the region have been purged and the Remnant fully wakes up. The more complex Dregs are also able to hurt Rei if she stays too long on it, turning red and hurting her. The Remnants are made up of the Dreg slime, covered in white bone like an exoskeleton that protects its viscous oily "flesh". Like with the Dregs that need to be purged to gain a Remnant's attention, the Dreg slime of the Remnants have nerve endings that need to be struck to weaken it and break its exoskeleton.
A lot of floor and walls in the Ultravoid are covered in portions of Dreg slime that does not seem to be connected to any complex lifeform, seemingly being dead Dreg "tissue". This Dreg slime can be climbed on. It cannot be skated through, however, and jumping from the Dreg slime that is on the ground is hard as it clings onto Rei.