The Oasis was founded when a bunch of wanderers stumbled upon the ruins of an ancient Blackstone site, human-sized buildings resting on a treasure trove of water crystals. Enough crystals to support a burgeoning society for years to come. In addition to its plentiful water supply, the place that would become Oasis was surrounded in a perfect circle by hardy Blackstone walls. One of the original settlers, a leader and philanthropist, as well as Argent’s ancestor, claimed the green expanse for his own and constructed a modest house in which to live. The rest of the wandering band holed up in the remnants of buildings around the city, patching holes and unfinished spots with tents and fabrics to keep the sun out. Roads half-buried in the sand created subtle divides between the various districts of Oasis.
The market sprang up in the space practically empty of Blackstone remnants, comprised of tents with tables or other erected furniture to hold the wares of merchants. Sometimes sand is swept out of the tents to keep the ground even, but most of the work is done by the sheer traffic that passes through the market.
The residential area was mostly made of old Blackstone buildings that the settlers began to fill. Holes, large and small, in the houses are patched with canvas or expanded into entirely separate rooms via tacking on a tent. Usually through an entrance that already exists, as Blackstone is currently nigh impossible to cut or alter. Even so, some way or another the homes barely resemble their original structures, as altered by people living there as they become.