Tiyanak or Impakto is another mythical creature in the Philippine Mythology similar to Greek mythological siren that lures prey with its voice. People get drawn into the deep woods to rescue the baby when they heard the sounds of baby cries. Some stories say the person wanders aimlessly in search for the baby and becomes hopelessly lost. Other stories claim that the person eventually finds a baby in the middle of the woods. The baby suddenly transform into a hideous monster with large pointed teeth when being found. It then eats the person and transforms back to a baby to await its next victim. With either version, the story ends with “… and he was never found again.”
Tiyanak are babies who died before receiving baptism rites. After death, they go to a place known as Limbo, a chamber of Hell where non baptized dead people fall into, and transformed into evil spirits. These phantasms return into the mortal realm in the form of goblins to eat living victims. The Tiyanak can also be the offspring between a demon and a human.
The Tiyanak can also be the offspring of a woman and a demon. It can also be the aborted fetus, which comes to life to take revenge on its mother. Tiyanak are very vengeful creatures. Most Tiyanaks are said to live in forests. If they see a human, they transform into what looks like a normal baby. When the person notices the Tiyanak and comes near to take a look at it, that's when the Tiyanak changes back to its true form and eats its prey.