Slurk

Long ago, dwarves dragged giant forest toads beneath the earth and altered their physiology with powerful magic in hopes of creating powerful underground beasts of burden that would be perfect mounts. The slurk is the disgusting result of their aborted efforts. The creature's unappealing slime and foul reek caused the dwarves to drive away their creation in disgust. Kobolds, on the other hand, are less picky, and frequently use slurks as mounts to this day.  
 

Appearance

Slurks are oozy abominations resembling pale, slime-slick toads with enormous, saber-like teeth. With the slurk's natural ability to climb walls and cling effortlessly to ceilings, it can be easy for unwary cave explorers to end up on the wrong end of these formidable ivory tusks.   Slurks exude two very different types of foul-smelling secretions from their pale white skin. Large pustules on the slurk's back drip a sticky resin-like slime that quickly hardens upon exposure to air. By flexing its skin, the slurk can burst these pustules in the direction of intruders, covering its foes in sticky goo and severely limiting their ability to withstand the monster's other attacks, including the effects of its other secretion. Glands along the slurk's ventral side excrete an incredibly slippery and fetid grease, which protects the slurk from the immobilizing effects of its own back slime but also has the added benefit of making it extremely difficult to grapple and capture. The best way to discover if a slurk is in the vicinity is to look for hard clumps of such grease, which accumulate and dry in cave corners and amid rock piles where slurks rest between meals.  

Ecology

Slurks are thought to be descendants of a failed dwarven attempt to domesticate and breed large subterranean frogs as food and labor animals. Despite this apparent failure, others who live underground often befriend slurks. The sticky frog-beasts have proven extremely desirable to kobolds, who now domesticate and train slurks as powerful mounts and guardians. While other creatures, particularly boggards, sometimes train slurks to serve as guardians, kobolds remain those who use these creatures the most. A kobold mounted on a slurk will often hide in the upper ledges of a cave, using the advantages of height and surprise to harry foes with ranged attacks. Kobold riders also take advantage of the slurk's ability to climb, and charge at their enemies from the walls of a cavern.   They are sometimes bred like cattle by those who do not mind their rubbery, yet nutritious meat, or kept as pets or mounts. Slurks eat mainly lichens and fungi.
Geographic Distribution