What is the scariest thing about ancient Greece that archaeologists have discovered?

 I don't think the archaeological finds are scary (I think I said that before…), but in the archaeological site of Anemospilia (Crete) the remains of a Minoan temple were found, destroyed by an earthquake around 1700 BCE.

The temple consisted of three chambers (east, central and west) and an annex: the eastern chamber contains the remains of amphoras with votive offerings; In the annex, the remains of someone who was crushed by a rock when he tried to flee during the earthquake were found; and in the central chamber the remains of more offerings and the ashes of the wooden idol that occupied the altar.

And the strangest thing was in the western chamber:

…Two skeletons were found on the floor, one in the southwest corner of the room. This body was of a 28-year-old woman; because the average life expectancy in ancient civilizations was around 55 years, she would have been a middle-aged woman. She could have been a high priestess of some sort.

The other skeleton was that of a man, he was around thirty years old, 183 cm tall and strongly built, lying on his back with his hands covering his face, as if to protect it. The tall man had an iron and silver ring on the little finger of his left hand and on his wrist an engraved seal of “exceptional artistic merit”, this would obviously have been very valuable. His legs were broken and his body was found near the centre of the room next to a platform (...)

At the top of the platform another body was found. This was the body of an 18-year-old man; he was found in a foetal position, lying on his right side. An ornately engraved knife was found among the bones; it was 40 cm long and weighed more than 400 g. Each side of the blade had an incised depiction of an animal's head, the snout and tusks of a wild boar, ears like butterfly wings, and slanted eyes like a fox's. His legs were forced back so that his heels almost touched her thighs, indicating that they were bound there.

More or less so:

They were in the middle of a human sacrifice when the earthquake buried them inside the temple.