Goliath Shev
With its armor, speed and sheer size, the goliath shev is one of the most fearsome predators of its time. Sustained by its multiple nuclei, it can grow to truly monstrous proportions: at 20 mm long, few creatures are greater in size. Only the Carpotesta luceremundare, Carpotesta devoratori, Binucleusdetritivorous Thornworm, and Binucleus Crystal Shrub exceed it, but none pose a threat to a fully-grown Goliath Shev.
Though it starts out looking much like its ancestor, it soon accumulates armor out of cellular wastes, sand, and cellular secretions (i.e., a thin mucus). Fully grown, its body is covered in thick armor, bumpy and vaguely brick-shaped. This armor makes a fully grown goliath shev practically impervious to attack. Should a goliath shev that's not fully grown come under attack, it can partly retract its pseudopods within its armor.
Its armor makes it nearly indigestible and distasteful to carpotesta devoratori, a rare predator. Fully grown, it's one-fifth the carpotesta devoratori's size, making it too much of a throat-clogging mouthful for the organism. (especially as it lacks any way to break it apart) Still, the carpotesta devoratori might eat younger goliath shevs, which are much smaller with less-developed armor.
Pseudopods or "tentacles" of cytoplasm allow the goliath shev to walk and capture small prey. "Packs" of goliath shevs may cross large colonies of mega binucleusdetritivorous, which form sheets on the seafloor, and slowly devastate them. The goliath shev needs only to stay still as a barely-detectable current carries tiny organisms to its top tentacles, where they are captured and dissolved.
At its immense size, it can "walk" along the bottom of the ocean floor, and simply scoop up and eat anything it walks over. Stronger currents allow it to bounce along the ocean floor like pieces of grit in the wind, travelling fairly rapidly.