Here's some characters in Philippine cinema who don't need costume on Halloween. Mind you, it's not because they are ugly or scary looking but because they have personified the horror creatures they are portraying.
1. Nonong Bangkay, the personification of an undead or Death himself.
He has been managing a beach resort owned by the town mayor for eight years now
2. Lilia Cuntapay, the scary and old white lady herself.
She starred in countless horror films including the Shake, Rattle and Roll series. She is also the lead star in the indie film "Six Degress of Separation from Lilia Cuntapay" which is actually quite good and gathered a lot of awards.
At first look she's just you're typical grandmotherly grandmother.
Until she opens her eyes and mouth wide.
She used to teach Primary School in Tuguegarao.
3. Palito (RIP), the embodiment of a living cadaver.
Palito mostly played comedic roles as a walking dead person on many Filipino slapstick films. He also had lead roles in action films (believe it or not) as Rambuto (A pun on Rambo and "buto" or bone) and James Bone (not the porn character).
For his characters he usually just put cottons wads in his nostrils or just wrap a white cloth around his head.
He was a musician and used to play live in stage shows in a casino in Sta. Cruz, Manila.