The substance known colloquially as Gateway Grease or Spire Sludge owes its existence not to sophisticated alchemy, but to the chaotic aftermath of the Shadow War. After the Dragonbone Vanguard successfully destroyed the corrupted Bukhara Spire Gateways, an extra-planar threat was quelled, but at a cost. The shattered crystalline ruins of the gateways began to bleed a viscous, magical ichor into the ravaged landscape of Coia. This runoff became the raw material for a desperate populace.

Opportunistic commoners and refugees, desperate to rebuild their lives amidst the war-torn ruins, began harvesting this ichor. They collected it in whatever containers they could find, from buckets to old wine bottles, recognizing its potent yet unstable properties. Though it mimics the legendary Oil of Etherealness, Gateway Grease is crude, inherently unstable, and deeply tainted. It carries the chaotic energies that once fueled the very Shadow War it sprang from.

It was on 15 April 1 that this harvested ichor officially began its journey as a recognized, albeit illicit, commodity. From this point, its trade flourished in the dark corners of society. Widely available in the back alleys of Ironhold and Rueside, it became a lifeline for those on the fringes. It served as a desperate substitute for proper magic.

Individuals unable to afford genuine magical solutions, yet possessing an urgent need to disappear, became its primary customers. Its allure lay in its promise of temporary invisibility, despite the inherent risks. Currently, this potent and volatile substance awaits its next transaction. It sits in a crate of assorted elixirs within a smuggler's hideout near the Iron Mountain, poised to be sold to an unsuspecting adventurer.