Another Fluctuation in the Emotions
The Crust-Mantles were a weak race, always on the receiving end as any and every Frenzy Beast was out to eat them. After all, their flesh was beneficial to the evolution of their Essence of Frenzy and was also able to increase their Nurturing rate by a little.
Therefore, the higher the Tier of a Crust-Mantle, the greater the tonic it proved to be for the other Frenzy Beasts. It was not to mention their strength was weaker than most of the battle-oriented Frenzy Beast races.
Therefore, the Crust-Mantles always had to live out in hiding, solely relying on ambush tactics to hunt their prey while depending on their tough carapace to tank out the attacks directed at them during the hunt.