When a rocky topographic feature — a mountain, hill, giant boulder, or even an outcrop at sea — plays an important role in a work of fiction, writers are prone to making its appearance unique and memorable. As few writers or viewers are geologists, saying it's made of such-and-such a type of stone can contribute little to the work, either descriptively or dramatically. Making it look like a creature, however, is sure to strike a chord with the audience.
This trope typically comes in two variants:
The geological feature looks like a tremendous creature, or part of one. Whether carved out by natural erosion or shaped by some long-ago civilization's sculptors, its resemblance sets the mood for the locale: a mountain shaped like a tiger evokes a different ambiance than one shaped like a gigantic fist, for example. Its distinctive appearance may be utilized in-story as a landmark for navigation ("Walk two miles towards the peak shaped like a horse's head..."). If it resembles a creature that is held to be sacred by the local culture, expect the terrain-feature to be considered holy as well.
The Monster Shaped Mountain actually isa tremendous creature, one that was either made of stone to begin with or Taken for Granite. If it's dead or merely inert, it may be overgrown with vegetation; locals might even have built homes on its surface, making the possibility that it might wake up and start moving a serious concern. In cases when the creature is openly known to be alive, it will often fulfill some benign protective role for nearby inhabitants. If the Mountain is intelligent as well as living, it's a type of Genius Loci.
Skull Rock in the various versions of Peter Pan, where Captain Hook takes the kidnapped Princess Tiger Lily.
In Naruto, the Land of Iron's signature landmark is the Three Wolves, a mountain that is shaped like 3 wolves' heads.
In The Incredible Hulk #261 Hulk battles the Absorbing Man on Easter Island. The Absorbing Man absorbs the Earth itself, but then Hulk bashes him into the sea, where he becomes a small, man-shaped island.
In some Marvel stories featuring The Mole and Monster Island, the mountain that leads to his underground lair resembles a monstrous face (complete with Cave Mouth).
Film - Animated
In The Land Before Time, "the rock that looks like a Longneck" is one of the landmarks that Littlefoot's mother teaches him to look for on the way to the Great Valley.
One of the worlds that the sea troll from The Colour of Magic observed while drifting through space was actually a continent-sized sleeping dragon, its mountain-sized spinal ridges capped with snow.
In The Light Fantastic, several trolls which Rincewind meets transform into vaguely-humanoid boulders when the sun comes up.
The Paps of Scilla, a mountain on the caravan-route from Zemphis to Ankh-Morpork, has stirred a lot of speculation about the lady in question, because it has eight peaks.
On a similar note, in Small Gods, Om directs Brutha to head towards a tall, erosion-shaped rock that looks... very unexpected, really. Apparently the wind god has a rather crude sense of humor.
In a small-scale example from Carpe Jugulum, a limestone formation in the shape of a witch sits near the entrance to a cave beyond the gnarly ground.
In Wintersmith, the titular elemental creates icebergs that look like Tiffany Aching.
Dzur Mountain is one of the major locations in the Dragaera series, and is shaped like the ferocious feline it's named for.
Adrilankha's name, according to Paarfi, was derived from how the cliffs on either side of the city's harbor resembled a bird's outspread wings. Subverted when one of the "wings" collapsed into the sea during Adron's Disaster.
The Prydain Chronicles novel The High King. Mount Dragon was so named because its peak was in the rough shape of a monstrous, crested dragon's head with gaping jaws, and on either side the lower slopes spread like outflung wings.
In Andre Norton's Storm Over Warlock, Shann Lantee first dreams of, and then sees, a mountain like an enormous skull. Winged creatures fly into and out of its eyeholes.
The card Hamletback Goliath from Magic: The Gathering is given to be this. The card art depicts a couple of goblins living on the Goliath's back, and plant growth that makes it look like a mountain.
In the RavenloftD&D adventure "Neither Man Nor Beast", the beach where the player characters become marooned on Markovia is covered with giant stone figures buried waist-deep in the sand or just offshore.
A short adventure from Dungeon magazine was located at the site where a huge dragon and the flying ship it'd attacked had crashed into a pool of lava. Several of the caverns in the resulting dungeon were shaped like dragon-parts, as the lava had congealed around its skull, limbs, ribcage and tail.
Graben Island, in the Ravenloft setting, is shaped like a three-clawed monstrous hand.
The entrance to the infamous Tomb of Horrors D&D adventure is through one of the openings in a skull-shaped cliff.
The Dragonlance game-setting has Skullcap, cranium-shaped site of a long-ago evil wizard's stronghold, and the cover of the module Dragons of Light features a huge dragon statue carved out of a mountaintop.
In the casual game Drawn: Trail of Shadows, one of the painted worlds is home to a mountain-sized stone giant with huts built on its shoulders. Events in-game have saddened it, so a slender waterfall of tears streams from its gargantuan eye.
In Icewind Dale, the dungeon of Dragon's Eye is much in the shape of a dragon's head, hence the name.
In the fourth Azada casual game, a path leads up a hill shaped like a giant canine.
In The Lost Crown, Saxton folklore holds that the jagged rocks along the shoreline are spines on the back of Grindle, a dragon from local legend.
In an episode of The Magic School Bus about erosion, the class's trip along a mountainside triggered a series of rockfalls and stream-diversions that re-shaped the terrain to resemble a human figure.
The Adventure Time episode "Memories of Boom Boom Mountain", in which the titular mountain is living, has a face, and cries boulders. A female mountain, also with a living face at its peak, appears as well.
Snake Mountain in the He-Man franchise; in the 2002 series, it was eventually revealed to actually be a giant snake frozen in place when King Hiss and the Snake Men take over.
Several actual terrain features, such as Mount Carmel in Connecticut or the mesas at Sibley Peninsula in Ontario, are nicknamed "Sleeping Giant" for their resemblance to a prone human figure.
The "Old Man of the Mountain" was a granite feature in the White Mountains of New Hampshire which, until the formation collapsed in 2003, resembled a human profile.
A photo from the Viking probe which went to Mars in the 1970s showed a feature in the Cydonia region which looked eerily like a human face, and was the object of a lot of Ancient Astronauts speculation, including a popular book on the subject. More recent photography of the area by probes showed a more mundane geological image, and that the face seen in the original was probably a coincidence caused by shadows.
Five hats means that five tropers think it is ready to publish.
You are saying that you think this draft is ready to be published. That means the description is not ambiguous,
it doesn't duplicate an existing trope, there are at least three examples, and the title makes sense.
Is that what you meant to do?
You are saying this draft has a ready-to-publish hat it does not deserve and you are taking it back.