The Batibat is a vengeful demon found in Ilocano folklore.
The batibat takes the form of an ancient, grotesquely obese, tree-dwelling female spirit.
When a person does sleep near it, the batibat transforms into its true form and attacks the person by suffocating their victim and invading their dream space, causing sleep paralysis and waking nightmares.
This condition lends itself to the Ilocano word for nightmare, "batíbat" (or bangungot in Tagalog).
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