when the world becomes too much of a kitchen sink

[King of Nowhere]

You are what you eat. After generations of a city living on a terrasque dominant diet, the people start acquiring terrasque features, like healing faster than their neighbor cities and their skin hardening into natural armor.

And having a 3 of intelligence, no opposable thumb, sleeping for months at a time and going on murderous rampages when they don't. why should they only get the best stuff?