Asked for chat for a challenge, Dusk and Daisie challenged me to do a background of Lumilens.

Lumilens is basically a mediaeval city in a fantasy setting I DM'd a while ago.

The core principle of the setting is that darkness means death as impossibly deadly creatures lurk it constantly.
More than 6 seconds in darkness means death.
To make things even more fun, there are no moon in that universe. Nights are pitch black.

Given all this, inhabitants must always rely on themselves to and have durable light sources handy.

3 greater cities however are sufficiently developped to provide illumination to its citizen in a collaborative manner. The 3 great cities of light : Lumilens, Fireburg and Manitari Mines.

Lumilens is the biggest and oldest but the most (literally) well-oiled machine of the three. It relies on a central lighthouse to provide illumination to its citizens which also doubles as a palace. The lighthouse is constantly fueled and its beams are redirected to citizens through an elaborate system of mirrors controlled mostly mechanically.

Despite the apparent safety the beams provide, Lumilens' current ruler outlawed the use of any other light source within the city. Any such device is destroyed and its owner, executed.

Thanks to a massive supply of oil, Lumilens has withstanded many sieges. Its preferred defensive strategy involves setting fire to enemy fuel reserves from afar by focusing sunrays.

TL;DR : I asked for something to do, chat asked for the most complex background theme ever because I said I should practice background. Had fun :)