Biological Horrors are aggressive, insectoid creatures found guarding Whispering Eggs (which contain valuable Larval Cores). While individually weak, they swarm in large numbers and can quickly overwhelm an unprepared player. Abyssal Horrors are their aquatic counterparts, found guarding Hadal Cores.
Strategy: The key is speed and area-of-effect weapons. Use the Scatter Blaster or Plasma Launcher to clear groups quickly. Build a small base with walls around the Whispering Eggs before harvesting to create a safe zone. Alternatively, use your Exocraft (especially the Minotaur) for protection and firepower. Grab the Larval Core and immediately boost away. For Abyssal Horrors, use your Nautilon Exocraft's weapons or a powerful Multi-tool weapon while underwater. Their attacks are less frequent but still damaging.