Fenleer is a compact Mapach with thick, oil-stained russet fur and dark patches around his eyes. He wears a custom suit of scale mail that looks cobbled together from varying metal sheets. His most striking feature is a large, brass-domed steam tank strapped to his back that powers several hydraulic appendages, including a reinforced mechanical arm that mimics his movements. He usually smells of coal smoke and ozone.

He is perpetually busy, his hands constantly fidgeting with a loose screw or a piece of wire. He talks with a rapid-fire cadence, often using technical forge-slang that leaves others confused. Despite his grimy exterior, he is remarkably social and has a knack for reading people. He views every problem not as a crisis, but as a puzzle waiting for a scrounged solution.

Fenleer began his life in a crate, abandoned among the rusted husks of weapons during a scrap shipment to Hiedenferg. While the nomadic Mapach tribes who sired him were lost to an ambush, the flying city of Hiedenferg became his nursery. He was raised in Lower Sector Seven by Astezoh, a stern Vulpin smith who saw potential in the kit. From the moment Fenleer could hold a wrench, he was obsessed with the Devenis Mechana festivals, watching the massive warships race through the clouds and dreaming of building his own titan of iron. His apprenticeship was unconventional. He learned the value of people and their hidden desires from a sharp-eyed kobold handler while negotiating contracts. By the time he reached adulthood, Fenleer had scrounged enough parts to assemble a functional steam-powered companion, an achievement that earned him a place in the Forgery Guild. However, the prestige of the guild came at a price. His immediate supervisor made a reckless deal with a rival city, putting the independence of Lower Sector Seven at risk. Haunted by the knowledge of this betrayal, Fenleer now travels beyond the clouds of Hiedenferg, looking for the components or allies needed to fix his home before the delicate machinery of its society collapses into the scrap pile from which he was born.