Harpy

Today's creature, of which you have to decide later whether it is from Hellas or not, is called the harpy.
On the one hand it resembles a bird, on the other hand a human.

Some of them have a really old and ugly woman as a component, forming their heads.
But there are also examples which appear with a beautiful virgin-head too.
However the look of the human part looks like, the rest of the harpy is basically a strong bird.
It has strong claws which even allow them to kill people.
In addition to that their flying-properties are quite optimal meaning that they can fly even faster than a storm.
They are said to be invincible but according to a story, one harpy gets killed nevertheless.
The harpies execute orders received from a higher force, mainly in order to take vengeance on certain persons.
So it came, that they tormented for instance king Phineus in following crucial way:
They stole his food.
But instead of leaving him nothing, what would have been rude enough, they left him just enough to survive.
As a result he was doomed to feel the pinch of hunger.

Now it is your turn. Do you think, that the harpy is part of the Greek mythology or not?