Derlacs were enormous marine animals, reaching lengths of up to fifteen meters. These creatures formed herds and subsisted on aquatic vegetation and insects found near the oceans surrounding Shaum Hii. The Kian'thar people domesticated derlacs, similar to how humans raise cattle. They would ride their bentail steeds and guide the derlacs using specialized derlac whistles. Kian'thar ranchers identified derlacs belonging to their herds using branding techniques, but generally allowed them to freely roam the oceans until they were needed for trade. Typically, a Kian'thar family would bring roughly twelve derlacs to the livestock market each year.
Derlac meat represented the primary export of Shaum Hii.