By all accounts, the Hungry Hill wasn't made, so much, as grown. From what it was grown, though, and who put the effort in to do so remain happily unanswered questions. Regardless of who made it, the Hill is out there and it lives up to its name.
Appearing as nothing more than a pleasant, grassy hill, this treasure is adept at both camouflage and deception. It changes its look with the seasons, covering itself with piles of multicolored leaves or gentle drifts of snow as the occasion demands. Only the slightest depression at the summit and its unnatural symmetry serve to warn the wary that something is amiss.
The Hungry Hill more than earns its name. Anyone foolish enough to venture upon it is in immediate and terrifying danger carefully hidden by a few inches of green grass or winter snow. Those who stop at the peak have only a few seconds to continue on their way before the maw of the Hill opens up and swallows them with a single gulp. Inside, teeth like boulders grind the unfortunate victim to pulp in a matter of seconds and all attempts at rescue prove futile. After all, one would have to physically dig halfway through a large hillock to reach the Hill's meal and there simply isn't time to do that before the question becomes moot.
Various individuals have attempted to do something about the thing over the centuries but, not surprising, none of the attempts have been successful. The occasional survivors don't talk about what happened much, but it would seem the Hungry Hill has friends, or at least allies.
Fortunately, there is only one Hungry Hill. Unfortunately, its rather more mobile than one would expect a hill to be. It has an unnerving habit of simply deciding to be somewhere else. Exactly how it manages to relocate is a mystery; how it manages do so while integrating itself perfectly with its surroundings even ore so. Still, the wherefores aren't as important as the fact the it actually pulls off the feat.