Aswang is an umbrella term for various shape-shifting evil creatures in Filipino folklore, such as vampires, ghouls, witches, viscera suckers, and transforming human-beast hybrids (usually dogs, cats, pigs).

[1] Spanish colonists noted that the aswang was the most feared among the mythical creatures of the Philippines, even in the 16th century.

"The sixth was called silagan, whose office it was, if they saw anyone clothed in white, to tear out his liver and eat it, thus causing his death.

Let no one, moreover, consider this a fable; because, in Calavan, they tore out in this way through the anus all the intestines of a Spanish notary, who was buried in Calilaya by father Fray Juan de Mérida.

Some live in forests far from human communities, but the aswang can infiltrate human society by means of marrying into a community, and either slowly draining their husband of blood, or else using it strictly as a hideout and leaving at night to raid other villages, thereby keeping their cover intact.

The weredog then kills and eats people, particularly pregnant women on the road in the night, and do not let their long hair hang loose.

Unlike the previous aswang, the weredog does not infiltrate human communities through marriage, but as a traveler of some sort, such as a peddler or a construction labourer.

[12] Aswang commonly dwell at night in locations such as cemeteries and woods, as their powers are significantly, or sometimes totally, reduced during the daytime.

[13] However, despite being described as wild monsters that often live in the wilderness and outskirts of society, aswang are also described as creatures that are capable of living within close proximity of or even within the confines of a village, leading to several reports of aswang attacks within large, populated towns and cities.

Their ability to adapt and live within the urban and rural environments populated by humans while still maintaining their feral, monstrous nature is cited as a feature that distinguishes aswang from most other monsters.

[13] Aswang are traditionally described as one-dimensional monsters and inherently evil by nature with no explicable motives beyond harming and devouring other creatures.

Aswang are described to be unclean and favor raw human meat to the food found in traditional Filipino culture.

Holy objects, spices, salt, ash, the tail of a sting-ray, large crustaceans, vinegar, betel nut chew, and urine are all listed as tools for protection against aswang.

One method is for the husband of the child-bearing wife to remain under the house naked while furiously waving a sword.

Additionally, sick people should not stay in houses with holes and are told not to groan in order not to attract aswang.

Recite secret prayers and throw all the waste into the ocean so that aswang cannot trace whoever made the oil.

Magic prayers can be used to make the aswang vulnerable; while it is in this helpless state, its body must be cut into pieces.

[16] Because of the archipelagic geography of the Philippines, and the primarily oral mode of inheriting and imparting narratives from the past for preservation or didactic purposes, stories about the aswang have evolved and adapted according to the locality in question.

[4] The aswang was born out of Philippine folklore, with stories of this terrifying creature dating back to at least the 16th century, when Spanish explorers created the first written record of the monster.

He called the Gods to help him put out the fire with rain and take revenge on the aswang by making thunder and lightning to strike the mountains.

[23] The KMJS team tried to substantiate the resident's claim by installing cameras to capture the alleged creature, but to no avail.

[25] Individuals diagnosed with this disease exhibit debilitating symptoms that put them in a "transforming state", which results in their "bod[ies] twisting, tongue[s] protruding from their mouth[s], [and] salivating.

"[25] With the disorder being endemic to the region for generations, the visible symptoms have been interpreted as a major contribution to the prevalence of narratives surrounding Capiz as the home of the aswang.

[26] Individuals afflicted with this disease are branded as aswang and are socially ostracized, which prevent their families from seeking effective medical treatment and forcing them to isolate themselves from the larger community.