Grindgill has adapted to feeding on crystal flora. Its mouth has moved ventrally and adapted to grind through crystal flora shells. The outer portion of the radula has become a concave disc with flat molar-like denticles arranged in concentric circles. The innermost portion of the radula has become a proboscis-like structure, covered in small dentin hooks. To feed, the Grindgill will clamp onto a crystal with its mouth and wrench itself laterally to grind down the crystals shell until a hole is made. It will then insert its proboscis into the mycelial innards to scoop out and eat the insides.

The body has flattened, and the tail tentacles have developed into a lateral fin running the length of the Grindgill. Its coloration has become much more muted so as to better match the substrate. Its tail remains purple as the quality of the color is an indication of health and strength to mates. Its eyes have become risen on stalks to give it a greater field of vision.