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.
Termites, in certain places, make homes that can be eight meters high and only a half meter wide. They are built facing North to South to take advantages of the suns travel, maximum heat in the morning and evening and little in the afternoon. Imagine grassy plains with vertical structions facing a certain direction all over the place. Ambush? Maze? New creature? Larger structures?