Yeth hound

Yeth hounds, or simply yeth, were intelligent outsiders that hunted during the night.

Description
The hideous yeth hounds resembled large greyhounds, standing high at the shoulder and weighing about. Their short fur was a dull, nonreflective night-black, often blending into the darkness and leaving only the cherry-red glow of their eyes and the smell of chilled smoke to indicate their presence. They possessed an oddly human-like visage, with protruding noses in place of muzzles and more flexible necks than those of canines. Their ears were short and pointed, curving upwards and away from the rest of the head in such a way that they resembled horns.

Personality
Yeth hounds were wicked hunters and fundamentally obedient creatures, following the toughest member of the pack with complete deference and consciously seeking evil masters so serve. Aside from that, they had no loyalty to each other and would not assist each other unless told otherwise. The only prize they sought from their prey were their terrified screams as they hunted them down and tore them limb from limb and any treasures found with a yeth hound were purely incidental.

Threats and intimidation were of no use against yeth hounds as they possessed only one crippling phobia Yeth hounds never went under sunlight even in the middle of a hunt and even if certain death awaited if they didn't. They made sure that there was always time to return to their dens before the strike of dawn and stayed there pacing or sleeping until night fell again. Not even the wills of their masters could persuade them to stay during the day.

Abilities
The iconic feature of the yeth hounds was their dreadful baying that filled those nearby with panicked horror. Their ghastly howls filled foes with such unbridled terror that they would take the most direct path away from the yeth hound regardless of the obstacles or hazards that stood in their way. Evil outsiders were typically exempt from the effects of their barking but mortals could suffer permanent trauma from the supernaturally imposed fear. Yeth hounds were capable of magical flight, silently and tirelessly pursuing prey by gliding slightly above the ground. Their superb auditory and olfactory senses paired with their frightening speed made them incredibly dangerous hunters.

Only enchanted and silvered weapons could truly harm a yeth hound, as they partially passed through ordinary weapons as if they were mist. Their fear of sunlight was rooted in its detrimental effect on them, as exposure to daylight could banish a yeth hound to the Ethereal Plane. Torches and light magic could not harm the nightly creatures but so long as the sun shone on the spot they disappeared from they would be trapped in the Deep Ethereal. Once the sun set once more, the yeth hound could enter the Border Ethereal where it could see and be seen by beings on the Material Plane but not interacted with. Only by finding a pack mate or their master could a yeth hound return to the Material Plane, and death on the Ethereal Plane permanently killed them.

Combat
Yeth hounds fought by biting their enemy. Their bites were aligned to evil and once bitten their enemy was in danger of being tripped by them without being able to properly react to it.

Society
Yeth hounds were one of the servitors of the drow deity Vhaeraun, whose realm was Ellaniath. Yeth hounds were also known to serve Eshowdow of Chult.

When not found alone or in a pair, they organized themselves in small packs consisting of several to a dozen members.



Suitably powerful fey could create them. Once created, they were given as a gift or reward to a person of the fey's choice. The receiver was often assigned the position of pack master of the newly created yeth hound pack and could direct the pack via telepathy, which worked as long as both the master and the hounds were on the same plane. Should their pack master die, they tried to gain a new one, usually a representative of evil like a vampire, hag or necromancer.

They couldn't speak but could understand Infernal, Common, Elvish and Sylvan.

Background
The yeth hound is based on the yeth hound of the folklore of Devon, a headless black dog known for its wailing.