Chilean monsters which I intend to stat out, D&D-ize, and otherwise systematizally banalify:
The Hide is an octopus that lives in the sea and has the dimensions and appearance of a cowhide stretched out flat. Its edges are furnished with numberless eyes, and, in that part which seems to be its head, it has four more eyes of a larger size. Whenever persons or animals enter the water, the Hide rises to the surface and engulfs them with an irresistible force, devouring them in a matter of moments.
(Frankly, I don't think D&D had nearly enough giant carnivorous octopi with numberless eyes.)
The Strong Toad is an imaginary animal different from other toads in that its back is covered with a shell like that of a turtle. This Toad glows in the dark like a firefly and is so tough that the only way to kill it is to reduce it to ashes. It owes its name to the great power of its stare, which it uses to attract or repel whatever is in its range.
(Because D&D plainly also doesn't have enough luminescent giant Strong amphibians.)
The Alicanto is a nocturnal bird that seeks its food in veins of gold and silver. The variety that feeds on gold may be identified by the golden light that gleams from its wings when it runs with them open (for it cannot fly); the silver-feeding Alicanto is known, as one might expect, by a silvery light. The fact that the bird is flightless is not due to its wings, which are perfectly normal, but to the heavy metallic meals that weigh down its crop. When hungry it runs swiftly; when gorged it is hardly able to crawl.
(Because D&D also plainly doesn't have enough birds that eat precious metal.)
My favourite is the Hide, because monstrous octopi are just brilliant. Oh, what the heck, let's stat the thing out.
Alignment: Neutral Evil
Intelligence: Very (11-12)
No. Appearing: 1
No. of Attacks: 8
Special Attacks: If the Hide manages to hit the same opponent with four of its tentacles, it has engulfed the unfortunate creature and will proceed to consume it. It does this within three rounds, during which time the victim loses 33% of its hit points per round. If the Hide loses 50% of its hit points during that period, it releases its captive alive.
The Hide can also spray an ink cloud once per day. The cloud has the combined effects of a Darkness, 15' Radius and Stinking Cloud spell.
Special Defenses: The Hide has tough, rubbery skin and suffers only half damage from slashing or bludgeoning weapons. Piercing weapons do normal damage.
Hmm, maybe I'll give him more hit dice...