Famous myths

Chupacabra

The Chupacabra (from chupar "to suck", and cabra "goat") is a "cryptid" (an creature whose existence is unconfirmed but has been suggested) that has been found in many locations in the Americas. The animal has a reported habit of killing and draining the blood of livestock, especially goats. It is rumoured to be a heavy creature, the size of a small bear, with a row of spines reaching from the back down to the tip of the tail. The main source of sensationalism comes from the conditions of the corpses left behind. Sheep were found with 3 puncture wounds in the chest and left completely empty from blood.
We could bring this to our idea by forming the character's perception of the film's "creature" by the effects it leaves on its surroundings; possibly by the people or animals it kills to the destruction or clues it could leave in its path. The different things characters find would help to make their individual perceptions of the creature more varied.

Yōkai

Yokai are demons from Japanese mythology. They relate to our plot idea because a group of them called Henge, a kind of shape-shifting animal who imitate humans, mostly women. The legends could have some significance to characters in our film who are aware of the Henge myths, for example, someone Japanese or someone from the new stereotype of western people obsessed with Japanese culture. They could bring an approach to tackling the creature in the film that would help us form a narrative arc for that character.

Hybrids

Hybrids are combinations of different parts of naturally occuring animals. Examples are centaur (human and horse), gryphons (bird and lion), and mermaids (obviously, fish and human). These could be valuable influences to our film idea because it could be a way for characters ti visualise the creatures by piecing together things they are familiar with in real life to create something new. If we felt like going even further we could use this metaphorically as a subtext, referring to the process of making a high-concept film.