Prophetic Bird

These beings - large birds with crowned female human heads, dark, feathery wings, and frightfully effective talons, were transformed from the Apples of Paradise when the Yokels tried to pluck them off the Tree of Paradise without first having performed a blood sacrifice, as was required. Three apples were picked during that encounter, and all turned into prophetic birds. One was slain, but two are still there in its branches, guarding the apples.
Aside from sharp talons that rend flesh, the birds sing a mournful song about the apples not being accessible to mortals, who will descend into the Land of the Dead (Nav') for their feeble efforts. The birds possess other magical powers as well - they are quite effective at rendering others' spells inoperable, and as their name implies, can see the future.
They show no interest in chasing down retreating poachers, nor do they stand in the way of a picker who has performed the blood sacrifice.
If the birds have other names, they are not known. Their origin is likewise mysterious, though the life-draining effect of their songs suggest some sort of linkage to the Underworld.