The Ruin were an unintelligent species, similar to the Bane.
The Ruin had bright orange bodies shaped like an hourglass, with an opening at each end from which fleshy tentacles emerged. They had six long, jointed, black legs that splayed out from the waist. They grew so large that their bodies were the size of a van. They were parasitic and could lay their eggs in a human's gut. (PROSE: Dominion)