Nightmare Haunt

Nightmare Haunt
Nightmare haunts are terrors from the minds of Eldraine's sleeping citizens, made tangible by the planeswalker Ashiok. These creatures can hurt the body and also attack the minds of dreamers afflicted by the Wicked Slumber.
Nightmare haunts appear as horrifying shadow creatures with forms evocative of their victims' deepest fears. Due to the collective trauma experienced by the people of Eldraine during the Phyrexian invasion, many nightmare haunts take the shape of those terrifying invaders, having multiple limbs and inhuman visages. Smoky purplish energy wafts from their forms, suggesting their connection to the Wicked Slumber.
The Wicked Slumber
During the Phyrexian invasion of Eldraine, the high fae monarch Talion, the Kindly Lord, and a trio of witch sisters performed a grand ritual to create a sleeping curse. Even with the Phyrexians defeated, the curse remains and spreads unchecked through Eldraine due to interference from the planeswalker Ashiok and Eriette, one of the witches who helped create the curse. The Wicked Slumber affects rich and poor alike, causing them to fall into an endless sleep or roam as sleepwalkers. Animals are also affected, and even tree boughs droop as if exhausted in areas where the Wicked Slumber is prominent. Purple tendrils of wispy nightmares spread like vines across those areas and surround the bodies of those who sleep.
Heroes throughout Eldraine have ventured out to find a cure for the Wicked Slumber, but no one has yet discovered how to break the enchantment. It has even affected one of the Kindly Lord's daughters, the famed duelist Obyra. Meanwhile, Eriette and Ashiok conspire to build a nightmare realm in the ruins of Castle Ardenvale at the heart of the Wicked Slumber, replacing the virtuous court with one composed of sleepwalkers and dreamers guarded by nightmare haunts.