Even as humans can be, the Kel'Regar, too, can be touched by madness, and it can drive them to push to ends incomprehensible by the sane. The work of one such, Kararemi'ar'Salm'Torat, the Menangerie of Mad Creation, is a twisted, living structure, tormented by years of loneliness and incomprehensible need.
A world where, instead of aging in years, the people age in knowledge. So, instead of dying once a general age was reached, they die once they achieve a certain amount of knowledge. A man could live forever if he never learned anything, or could die after reading a few choice books. Of course, the knowledge of the land would be regulated, like medical drugs.