It is well known and documented throughout the empire of Thelitia, particularly around the desert's edges and radiating from it, beneath the looser ground, among the greatest threats to the merchant trains and nomadic peoples inhabiting those regions, are the massive "Sand Sharks".
These monstrous armored beasts do not resemble their aquatic namesakes in any fashion save for a large "fin" that is more akin to a spade, which becomes visible as the monster nears the earth's surface in pursuit or as to encircle, panic and or herd its prey before bursting from 'neath, all claws and great maw. Its speed and deadliness cruising through the earth, e'en as its namesakes slices through the sea, has given rise to its formal name. In the original Thelitian, the monster is called "Kadj'ik", or "Bulette" in the tongue of western men, after the deadly metal shot used in the traditional battle-sling of the Thelitian tribes.
The Bulette seems to possess a great taste for the meat of both horses and camel, though will happily feast on men, dwarves or any other flesh of any other beast, bird or reptile, t'would seem. I was given a tale from one Thelitian trader of silk of seeing a bulette entangled in heated battle with one of the fearsome giant desert salamanders. Thankfully, as the trader told it, they were too enraged and entwined with each to the other to notice the terrified man and his caravan of wares and made quick his escape from their view. But, he averred, the bulette appeared to be winning.
The creature, as best can be seen when fully above ground, which it seems loathe to do, has four legs. Each ending in a three toed foot of claws of adamant. The forelegs have a fourth thumb-like protrusion, allowing it to grip and grab at its prey and hold fast. The size of the creature is such that these fore paws (if they may be so called) might grip around the girth of a horse or camel, perfectly.
The aforementioned "fin" is of a similar bluish-grey, metallic appearance of its talons, as are the grey and brownish plates which cover the entirety of the creature's face and body, more heavily armored than e'en a tortoise or the legendary bonnacon. Its face, as I said, possesses a pointed, almost beak-like appearance, with a mouth that rounds from side to side, lined all along its perimeter with pointed flesh-rending fangs, much akin to that of an alligator.
The tunnels left in the wake of their underground passage have been the source of many a sink hole and invariably cave in behind the creature's passage. It is said, the observant can notice a bulette's territory by the streaks of sunken ground crisscrossing through an area. The only advice I have for those finding such a place is to turn around and leave before any rumbling begins or sand-shark fins break the soil. They do not seem to have lairs, these creatures. Moving ever-forward, they care nothing for treasure or riches. So, for the adventurous, there is nothing but pain and death to be had by encountering these monsters. They seem to have no discernible intelligence beyond the instincts of the basest animal, driven, solely, to feed. The only bribe that might catch their notice might be one of a sufficiently appealing foodsource.
The creature's underside, which stays always beneath or very close to the ground, is softer and might be pierced by such weapons as any prudent man surely has with them when traversing the Lost Sands or surrounding savanna. Even so, I have not yet encountered anyone who knows a tale of defeating such a creature.
In almost every case I have found, the only way to "defeat" the bulette is to flee and pray to whatever deities one holds dear that there is something else near you to chase, which is slower than you.