Echohawk just sent me another article, so we're off to the races...
Demons
Filipino demons seem to be creatures of a highly magical nature rather than inhabitants of another plane. Many of them live in large trees, and they are rarely pernicious or evil, content for the most part to frighten away those who intrude on their territories or fail to treat them with due respect, and only killing when greatly enraged. They are great pranksters.
All Filipino demons can become invisible at will, and each has a personal charm or jewel which is the source of its strength. If this can be won from the demon by wit or force, it will give the bearer the same strength (typically in the region of 18/01-23 -- the DM may select according to the power of the demon or roll on d6). Bright sunlight banishes them.
While the DM might rule that Filipino demons should be turnable on the "Special" line of the clerics vs. undead matrix, they do not seem to be deterred by holy symbols, and some actually delight in collecting numbers of them from frightened villagers.
Agta (Demon)
Freq: Very rare
# App: 1
AC: 3
Move: 12"
HD: 8
% in Lair: 90%
Treasure type: R
# Att: 2
Dmg/Att: Variable
SA: size change, fear
SD: size change
MR: standard
Int: average-very
Alignment: Chaotic neutral
Size: variable
Psionics: nil
Level/XP Value: Agta: VII/1450 + 10/hp; Kapre: VII/1900 + 10/hp
The Agta, Bawo, or Ungo appears as a muscular, black-skinned humanoid, and can vary its size instantly between 1 ft. and about 30 ft. It is generally about 10-12 ft. in height, which may be its natural size.
As it increases in size, it becomes stronger, as follows: when it shrinks to 1 ft., it has 2 hp, attacks as a 1 HD monster, and causes 1d4 damage on a successful hit. It can enlarge itself to a maximum height equal to half its maximum hit points (as rolled on 8d8) in feet, i.e. an Agta with 54 hp can reach a maximum height of 27 ft. For every 4 ft. of its height it attacks as a monster of 1 HD and cause 1d4 damage. Thus, at 1-4 ft. it attacs as a 1 HD monster and causes 1d4 damage, at 5-8 ft. it attacks as a 2 HD monster for 2d4 damage, and so on, up to a maximum of 8 HD and 8d4 damage.
Agta live in large trees, particularly favoring banyans and mangroves, and resent any interference with their trees. They attack with two fists, and on a successful double attack can rend as a Carnivorous Ape (Monster Manual), causing additional damage as for two successful fist attacks.
Another type of Agta is the Kapre or Pugot, which has a shapechange ability in addition to the Agta's size change. Its favorite forms are those of a dark cat, dog, or boar, which has fiery eyes and breathes blue-green fire, a pure white fowl, or a headless and often mutilated corpse. In this last form it will caper along, singing merrily to itself and eating by pushing food into its bubbling neck-stump. Characters of less than 4th level who see it in this form must save vs. spell or flee.
Both forms of this demon can also emit a great roar once per turn, which causes fear as the spell unless the appropriate saving throw is made.
One favourite trick of the Pugot is to rush between the legs of an unwary traveller in its boar form, increase its size and carry its victim off, never to be seen again.
From Imagine Magazine #25 (1985)