The Black Tar

Also known as Zeftmensch — a term meaning "Human-Tar" in the tongue of those who understand its origin — the Black Tar is a malevolent, semi-sentient substance that formed from the accumulated misery and souls of those who died in the Farseas swamp over centuries.

Nature

The Black Tar is not simply oil or pitch, though it resembles both. It is a spiritual substance as much as a physical one: the concentrated residue of suffering, formed by soul-wells in The Black Fields and fed by the deaths that the swamp's history has produced in abundance. It mutates life exposed to it over time. It powers dark technology when refined. It has been used — or at least coveted — by Thayan researchers as fuel for tar-warped undead armies and battlefield-spanning tar teleportation networks.

Its refined form is oil-based and pink-slime-like in consistency, stripping away the dark surface appearance to reveal something that looks almost organic.

Connection to Sigma Irungarten

The Black Tar is directly connected to the fall of Sigma Irungarten, whose fragmentation of his consciousness into objects — a desperate attempt to combat the tar's spread — led eventually to his evolution into Migma, a scattered mycelial intelligence that became one of the swamp's most significant threats. The tar fed his fragmentation; his fragmentation fed the tar.

The Crisis

The sabotage of The Farfetcher Pumps by Thayan agents embedded among the Drovers of Silverpool allowed the Black Tar to rise. Without Hydracephelate flowing through the pump network to neutralize it, the tar spread through the swamp's waterways, mutating flora, empowering undead, and threatening to consume whole settlements. The crisis defined much of the first three seasons of the The Farsea Chronicles.

Resolution

The Black Tar was neutralized at the climax of the The Iron Garden arc, when Rutherford Farfetcher's pump repairs were combined with a rewiring of the Hydracephelate dispersal system. The substance has been suppressed, but not destroyed. The Soul Wells in the Black Fields continue to feed it slowly, and under the right circumstances — or the wrong ones — it could rise again.

The Name Zeftmensch

The name "Zeftmensch" is known only to scholars and certain old-blood Drovers who preserved the term through oral tradition. It is a word from an older swamp creole, predating even the current Drovers, and its survival says something uncomfortable about how long the people of the Farseas have known what the tar really is.