Steamback
Ntari locals call it the Steamback, a trilobite-like grazer that lives around the planet’s hydrothermal fields. A shuttle-sized oval with tiered carapace plates, each ribbed and mineral-encrusted, and a shovel of a head shield for plowing through vent chimneys. From scraps of shell and gut stone taken off beach-washed carcasses, fishers think it feeds by grinding the mineral mats and tube-fauna that coat the vents, then wicking superheated water through heat channels under the plates to leach nutrients. The shell is dark, heavy, and pitted like slag; edges show regrowth bands, suggesting it survives partial plate loss and keeps armoring up across decades.
It only comes up to the surface to vent: a slow breach followed by clouds of scaldering steam that fogs a few hundred meters of sea. The Steamback reacts to engine hum and hull magnetics as a threat; it turns on the signal, rams with the head shield, and follows with two serrated fore-mandibles used to pry at plating. Lines of ciliated pits along the frill plates likely sense vibration and heat gradients, which tracks with how quickly it homes on working winches and live nets.
Ntari fishers warn to not work the “boiling lanes” where the sea goes brown-green and slick with rainbow films. If the surface around you ghosts over with warm fog and the deck starts to grit, kill engines, power down winches, and drift. Fisher crews carry decoys: a thermal drum or a spar buoy with a vibro-motor; either will pull the animal off long enough to restart and leave. Meat from the rare carcass smells of sulphur and makes folk sick; the only value is the plate. Good for stove tiles and patchwork hull skirts, but it’s generally considered not worth hunting.