The Mandible Maw was constructed around 104 CR, emerging from the tumultuous period known as The Great Harvest, which immediately followed the cataclysmic Dragon's Fury. This formidable gateway serves as the solitary entrance through the ossified, impenetrable walls of Hasaldon. It was masterfully fashioned from the calcified lower jaw of a colossal Black Dragon, a beast slain near the Iron Mountain. The dragon's mighty teeth were repurposed as the foundational structures for its formidable guard towers, creating an awe-inspiring and intimidating barrier.

For centuries following its creation, the Mandible Maw has functioned as the brutal and unforgiving filter for Hasaldon's strict meritocracy. Entry to the city is strictly granted only to those willing to pay the Marrow Toll, a demanding tribute requiring either rare skeletal matter or a demonstrable display of lethal prowess. More than a physical barrier, the gate is considered a spiritual threshold; locals believe that passing through the dragon's gullet strips travelers of their soft flesh and weakness, preparing them for the harsh realities within the Freehold. This enduring system has shaped generations of entrants.

Throughout its long and imposing history, the Mandible Maw has consistently upheld these rigorous entry standards, its presence a constant symbol of Hasaldon's demanding nature. In the present day, the Mandible Maw remains a formidable obstacle. It is currently under a state of heavily guarded, xenophobic lockdown, further solidifying its role as an impenetrable and unwelcoming gateway to the city.