The Harvester of Sorrow

The Harvester of Sorrow is an old tale told around many farming communities, along with some huntering & fishing communities, throughout Europe. She is seen as a spirit of nature, governing some of the darker aspects of nature. She is meant to appear when harvest time comes and the harvest is not enough for the coming year. She is seen to feed on the sorrow & despair of the community, and in many cases demands a blood sacrifice to leave them. Sometimes the blood sacrifice may require multiple individuals to appease her. If this is broken for any reason, there is the chance the Harvester will wipe out the community.
This happened recently to a settlement southwest of Aachen. In the year 800 AD about August / September time, a small settlement made up of farmers & hunters came to the point where they could not meet their quota for the year. They had suffered from Saxon attacks ranging far behind the Frankish lines, and the taxes to pay the Frankish army.
Fearing that they might starve or have to heavily ration their food stores, they knew it would be hard times ahead. What they didn't reailse, when it came to the time of Harvest celebrations, they did what they could celebrate. This included sacrificing a couple of goats, and a couple of Saxons they had captured after their raid on the small market village.
Setting this up, the people arrived at the sacraficial grounds and the small standing stone. What they soon realised was that they weren't alone in the grove. Resting against the standing stone near the goats & prisoners was a humanoid being with what appeared to be leather-like brown clothing, root-like growths on her shoulders, neck, and head. The pale gray skin looked barely alive, and then she opened her eyes. Gray-black eyes peered out, and then she spoke. With a leaves in the wind like voice, she asked if this was the sacrifice for the year. The villagers looks aghast and said yes, that they couldn't get any more. Looking at them directly, she stated that they need three more. An elderly villager, an adult, and a child. If not then they would suffer in blood to restore the harvest for the following year.
The creature seemed to disappear in & around the stone, leaving no mark of her passage. The villiagers & farmers bickered for a time about what to do yet decided that they were doing what they always did every year. That, and they were already strained without having to decide to kill anyone they weren't prepared to.
What happened next was horrifying. After making the sacrifice, the creature caused the fields to grow wild in a matter of hours with thorny plants that started whipping out grabbing the locals. Each one was captured & held while the creature walked out amongst this terrible 'fruit' hung there helpless. The thorny plants moved & dragged the villagers together in full view of her, who proceeded to that she was there to harvest her own crop, their sorrow.
So, starting with the livestock, then the young, she had the plantys rip them appart. Then the elders were. The adults were next. All that was left was the local clerics. She had them ripped appart slowly for their disbelief in what she promised. One hunter survived, watching from a road leading to Aachen.
There he fled to tell the story.
Others confirmed the nature of the creature, the Harvester of Sorrow. She came to make sure the sacrifices of blood are made correctly. If not, she pays such visits to punish the community for their hubris, and the necessary payment is made in blood.

"Always pay in blood to you god or gods. Look at the Harvester of Sorrow. She makes you believe you follow the correct path. A spirit, a deity, am angel or demon. Nobody knows. She could even be a Fey. But always follow it right, the Harvest Festivals. Or she will come."
Druid Emma Duckthorne, at the Grove of Eschbach.