Zaun is a large, undercity district, lying in the deep canyons and valleys threading Piltover. What light reaches below is filtered through fumes leaking from the tangles of corroded pipework and reflected from the stained glass of its industrial architecture. Zaun and Piltover were once united, but are now separate, yet symbiotic societies. Though it exists in perpetual smogged twilight, Zaun thrives, its people vibrant and its culture rich. Piltover’s wealth has allowed Zaun to develop in tandem; a dark mirror of the city above.