Why it evolved

With the collapse of its usual chemosynthetic food source, the Gloom Glutton has evolved a significantly enlarged and hardened radula, along with an extendable proboscis, to actively scrape and consume tougher organic matter like decaying plant material and fungal growths. This increased foraging ability comes at the cost of a reduced exoskeleton, making it more vulnerable to the acidic precipitation of the Weeping Canopy, and requires a higher metabolism to support its more active feeding strategy, demanding a more consistent caloric intake.