The Tulu are an evil and devious race, demonstrating the canny wickedness of Faustian devils and the perverse pleasures of hentai tentacle pornography.
A portmanteau of the words Architecture and Ecology, arcologies are megastructres that are built with an eye towards environmentally friendliness.
During a storm the PCs come upon a little boy that plays in the rain. Upon further inspection they discover that he has one eye and a long tongue lolling in its mouth. Spit dripping. It is a demon from beyond that can access our realm during storms, it eats all heads that are not its own, living and dead.