Bridge Hound

"'Initially, I thought the creatures desire to rend flesh was a primal instinct to seek sustenance, but after further studies bridge hounds require neither food nor water. I now believe that the drive for their violent tendencies come from some form of pleasure they derive from hunting.' --Professor Pealy Monix, A Midwinter Dissertation on Extraplanar Ecology, 1013 AE"

Overview
Bridge hounds are the beast of hell that roam the demi-plane known as The Bridge. In their plane they are fearsome hunters that hunt lost souls who have failed to cross the bridge. When they are summoned to the material plane of Ilderon they appear as massive hounds composed of liquid smoke, and shadows. They are widely sought after on the black market. The essence that composes their body is a powerful venom, that when properly refined, becomes a powerful medicine.

Keen Hearing and Smell
The Bridge Hound has advantage on wisdom (perception) checks that rely on hearing or smell.

Bite
Melee Weapon Attack: +4 to hit, reach 5ft., one target. Hit: 1d12+2 piercing damage. If the target is a creature, it must succeed on a DC 12 Constitution saving throw or be affected by Bridgebite. A bridgehound only produces enough essence to afflict one creature per day with bridgebite.

Claw
Melee Weapon Attack: +4 to hit, reach 5ft., one target. Hit: 1d8+2 piercing damage.

Bridgebite
When the bite of a bridge hound goes untreated, the venom affects the body with a chronic disease that develops through several stages. In it's early stage the bitten body becomes hyper active allowing the host to fight past wounds that would normally be mortal but also spreading the venom through the body. The second stage of the disease the body becomes resistant to magic. The third stage, the host is affected by the sickened condition as the venom loses its viscosity and begins to harden throughout the body. Depending on the amount of venom initially transferred to the host, during stage four the host has a chance to be petrified, stalling the spread of the disease. Those who are not petrified have their hit point maximum halved. The final stages of bridgebite result in death.