Backstory & Lore Backup

The Wailing Darkness   (Wailing Nightmare or Death  as told by other victims). 
The Wailing Darkness is a destructive phenomenon with little known yet about it or its dark origins. Tales and lore passes few lips as few survivors are ever left.  
Place of origin: 
The Shadow Wilds. It is thought that The Wailing Darkness comes from a place so deep and down in the darkest depths of The Shadow Wilds, few travelers have stumbled to deep into the woods thicket only to hear creaking twisted wailing in winds passing through a cave floor crevasse.  When the walls of stone can be heard getting traversed at  an unthinkable spread it is safe to presume they ran, only to pass on such wild tale of their discovery in The Shadow Wild.
Duration of attack: 
One hour every 5 years unless sated by a passing traveler unaware of its residence.  A single feeding of human size will postpone its emerging onslaught by 4 weeks.  It may attack on opportune chance if animals also pass its domain entrance.  Though feeding on animals barely sates it.
Appearance: 
True- Unknown Whiteness from a survivors account: Some who have lived to both see and tell the tale of The Wailing Darkness claim to have only glimpsed it for a mere fraction of a moment its body described as distorted pitch black darkness, elongated and sinister with no defining features. When questioned as to how one would see such a thing in an area where no light can be reached the response is  that this moment is in a fine line of death and survival where it is just parting to leave, Darkness starts to fade and it no longer needs to kill those that part with safety.  

Domain:  
Entrance a narrow stone cave crevasse deep in the heart of The shadow Wilds. Territory about 2 meters of entrance in an area span will trigger an attack, 10 metres will alert it of presence where it will sit in wait at entrance. Any cave system below entrance The Wailing Darkness will claim, this has never been mapped or fully explored but if another entrance were to be made or cave to collapse and connect it's opening up more space the Wailing Darkness will claim said territory in addition to original central living.  

Only one person has been said to have entered its domain willingly to find information on its existence and how it may live, a sorcerer by the name of Godarin who used his magic and knowledge of alchemy to hinder his trail. Godarin had scribed that the tunnels traveled were almost to narrow for him to traverse and that every waking moment despite his powers to conceal himself that the Wailing Darkness was hunting him. On decent cavernous winds would blow noxious air fueled by the scent of decay outward, When he had finally made it into a "room" the floor sloshed with a thick liquid paste that floated and pooled around the dead and their remains. Godarin attempted to path through other chambers and tunnels but the nearing dread of being another victim led the sorcerer back outside through the entrance he has first scaled down into, as his coat tail left the 2 meter mark he had noted how dark elongated fingers clasped the entrance and clawed an engraving trail back down into darkness. He still hears the shallow curdling growl and breaking stone to this day.