Champion of the Voidharrow

A Champion of the Voidharrow is a title given to certain lesser-demons made into demon lords, or Obyriths, believing that they would be granted enough power by the mad god Tharizdun to escape The Abyss. He would grant their wish and free them from The Abyss, though he tricked them and instead he would pour his thoughts into their minds, twisting them with his maddening power. Their memories are erased and their souls are reformed during this transformation to ensure complete subjugation. It was Tharizdun's plan to create champions loyal to his cause and order them to the material plane, in hopes that he could sew his seeds of chaos or even be set free. 

They typically took on the form of another creature from the material plane, usually that of a humanoid in order to gain the trust of others. There they would develop cults in the name of Tharizdun, though some feared others knowing of their masters schemes and would only refer to him as the Voidharrow. 

Though these demons wielded immense power, they were shackled by Tharizdun's will and essentially husks without a soul of their own. If one were to out live it's use, the connection of power would cease and the demon would perish forever. 

Names of Power. These champions would be given names by Tharizdun in the persona he created for them, though they differed. Although some of mention are Al'gonos, Alzel, Ise, Loce, Maldor, Rucel, Vucirteth, and Zothruzra. Though his true intention was to have complete control over the demons, for bestowing these names on them was a malediction. Simply speaking the true name of one of these demons was enough to put them into a daze, as such these demons took care to not have their names known.

Obyriths were an eldritch race of demons so ancient that they predated mortal life, and even the existence of the gods. Simply looking upon their strange shapes could drive a mortal insane, and even the cosmos itself was horrified by their presence. 

Tharizdun. Known as the mad god, or chained god, he is a long-forgotten interloper god who sought to destroy all that is. After he planted the seed of evil in the primordial expanse of the churning Elemental Chaos which eventually grew into The Abyss, and though the act gained him great power, his fellow gods temporarily put aside their differences in order to imprison him. He became trapped in another universe that had been completely subsumed by its own version of The Abyss, known only as Voidharrow. 

Voidharrow. The entity known as the Voidharrow is an abyssal plane and Tharizdun's prison, though it has been imbued with a fraction of the god's willpower. The Voidharrow manifests itself as a liquid, crystalline substance, that corrupts and twist those who touch it with Abyssal Plague, and turning them into plague demons. 

Abyssal Plague. This disease and its malevolence was divine in nature, it was usually fatal unless cured or until the victim was transformed into a plague demon. Should the infection take root, the victim began to grow dark-red crystalline sores that appeared to be laced with silver and contained flecks of gold. These sores spread across the body, causing the victim to become even more contagious, but they also became more resilient and willful. Infected creatures gained both unnatural strength and a desire to destroy all living creatures. Eventually, the victim would die and their corpse would explode, creating a fully formed plague demon. Those who survived the plague and were cured said they experienced a vision of an enormously powerful entity trapped in a void of darkness and desolation. They heard the whisper of this entity, who filled them with a desire to destroy every living creature. 

The simplest way to prevent the abyssal plague was to stay away from the Voidharrow or plague demons. Barring that, using divine magic was the only known way to prevent being infected by the disease. The only known way to cure the abyssal plague was exposing the victim to divine magic, but that only worked if the spell was cast before the plague had taken root in the victim's body at its later stages. The abyssal plague can be cured by any divine magic that would cure diseases. 

Stages of the Abyssal Plague. The Abyssal Plague has three stages.

• First Stage (0-30 days). The victim begins to grow dark-red crystalline sores that appeared to be laced with silver and contained flecks of gold.
• Second Stage (30-40 days). The disease cannot be cured at this stage. The sores spread across the body, causing the victim to become even more contagious. The victims Strength, Constitution and Wisdom scores increase by 10. The victim grows a desire to destroy all living creatures. 
• Third and Final Stage (41 days). The victim dies and their corpse explodes, creating a fully formed Plague Demon. 

If a creature carrying the abyssal plague were to die before transforming into a plague demon, that creature instead would become an Abyssal Plague Zombie. 

When a Champion of the Voidharrow creates their lair, they create a demiplane in the likeliness of the Voidharrow itself. The demon creates oozing crystalline spires and spreads pockets of disease throughout the demiplane and fills it with Plague Demons that await in anticipation of the mad god's liberation. Only a creature that knows the Name of Power of the demon that created the demiplane can access the demons lair, unless another means of entry is available. 

Lair Actions

On initiative count 20 (losing initiative ties), the demon takes a lair action to cause one of the following effects; the demon can’t use the same effect two rounds in a row:

• The demon detects the thoughts of all creatures within the lair and knows their locations. Creatures that are invisible or hidden gain no benefit from this condition against the demon until initiative count 20 of the next round.
• The demon causes up to four corpses within the lair to rise as abyssal plague zombies. (The creatures are zombies that carry the Abyssal Plague). These undead obey the demons telepathic commands, which can reach anywhere in the lair.
• The demon utters a dark word of Tharizdun's crazed thoughts. All creatures that can hear the demon must succeed on a DC 23 Wisdom saving throw or suffer from the effects of the confusion spell as if they failed the saving throw, which ends on initiative count 20 of the next round.

Regional Effects

The region containing a Champion of Voidharrow’s lair is warped by the magic of Tharizdun, which creates one or more of the following effects:

• Beasts within 1 mile of the lair become weak and sickly as if they were diseased.
• Plants within 4 miles of the lair slowly decay and ooze with a toxic red ichor. 
• If a humanoid spends at least 1 hour within 1 mile of the lair, that creature must succeed on a DC 23 Wisdom saving throw or descend into a madness determined by the Madness of Tharizdun table. A creature that succeeds on this saving throw can’t be affected by this regional effect again for 24 hours.

If the demon dies, these effects fade over the course of 1d10 days.

Madness of Tharizdun

If a creature goes mad in the demons lair or within line of sight of the demon lord, roll on the Madness of Tharizdun table to determine the nature of the madness, which is a character flaw that lasts until cured. (See the Dungeon Master’s Guide for more on madness).

Madness of Tharizdun