Slugs

Slugs are slow-moving mollusks commonly found near marshlands, wetlands, and damp environments throughout Middle-earth. Their behavior varies by region; some are passive, while others may act aggressively when disturbed. Slugs are weak to Fire damage but resistant to Cries, making them surprisingly resilient in their favored habitats.
These creatures inhabit areas such as Rushock Bog and the Marish in the Shire, as well as Eastern Malenhad in Angmar. They are also found in the sewers of Carn Dûm (Instance) and other distant locales, often thriving where moisture and shelter are abundant.
Despite their slow pace, large concentrations of slugs can impede travelers or disrupt crops, and some are prized by certain collectors for their unusual forms or utility in crafting.
A listing from the journals of travelers noting the varieties of slugs: