The Lorekeeper's Tome

The Bog Lurker is the half-glimpsed terror of the Ashen Marsh: a muck-cloaked horror that lies submerged in the mire, indistinguishable from the bog itself, until something wades within reach. Then it erupts in a spray of filth, seizing its prey in grasping limbs and dragging it down to hold it under the black water until it stops struggling. It does not chase and does not need to - it simply waits, perfectly hidden, in the one patch of mud a traveller was unlucky enough to choose. The marsh-folk read the safe paths by the absence of Lurkers, and the absence is never guaranteed.