These grow much like their ancestor: mats of cells with two nuclei, which all consume detritus as it falls on them. When they're on an inorganic surface, the mats just spread out into a film. Cells keep dividing in two and will continue growing upward over the existing mat, but this generally leads to the death of the lower layer. This can result in growing upward in layers of detritus, but the mat itself remains thin.
However, when Vailnoff mats get the chance to grow on something organic, usually a corpse of something fallen from above, they'll take the opportunity to grow right through it. New layers eat into the feast, as the Vailnoff mat spot grows and grows, consuming and filling it up.
Given their abundance, Vailnoff mats often come in contact with distantly related cells, and they've adapted to frequently exchange genetic material with each other.
In addition to spreading throughout Vailnoff's twilight zone, they've done well on the western coasts of Glicker. While they cannot consume living perfectogon crystalmats, they can still settle on one. This may be disruptive to its photosynthesis if they become thick enough, providing another check for their rampant growth. Vailnoff mats have not, however, found a good foothold to the west, as carpetesta occupies much of its niche in that area.