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Villains of Grim Hollow – Idmon
Sep 8, 2021

Article by Benjamin HuffmanThe evils that haunt Etharis are many, though rare are those who can stand against a party of courageous heroes alone. In this series, Villains of Grim Hollow, I’ll draw back the curtain on some of those uncommon antagonists that can go toe-to-toe with your Grim Hollow campaign’s player characters. In addition to the relevant rules, each article in this series will include the villain’s backstories, provide plot seeds to incorporate them into your game, and, of course, survey the sweet loot they drop if your party manages to defeat them.


Idmon lurks in shadows eating victim

Artist: Klaher Baklaher

“It used to be that the worst thing about being a target of the Red Hand was you’d never be seen again. Now it’s that when you are seen again, it’s because one of your killers is wearing your skin.”

Many years ago, the merchants of Altenheim warned travelers of a demon spider who preyed on those that strayed from the trade routes leading out of the city. These rumors eventually made their way to the Red Hand, an assassin’s guild loyal to the Ebon Syndicate. The leader of the Red Hand sent numerous gangs into the dense forest surrounding Altenheim to learn the truth behind these rumors. After several gangs failed to return, one came back reporting they had discovered a creature calling itself Idmon, who saw the region outside the city as his hunting grounds. The leader of the Red Hand and Idmon parlayed and came to an agreement: the skinweaver would create exquisite armors for the Red Hand’s assassins in exchange for a steady diet of humanoids and cultural artifacts.

In the intervening years, the Red Hand spread to other regions in the Bürach Empire thanks in part to Idmon’s craft. As demand for his work increased, so too did his pull within the guild. While he was at first content with monthly food offerings and common goods, he began to withhold his work until he was fed multiple times a week and brought rare tomes from across Etharis. To engorge the creature’s growing ego, some members of the Red Hand began to view Idmon as a divine being whose protection ensured the Red Hand’s ongoing success. These assassins offered prayers and worship to Idmon, even going so far as to declare their loyalty to him over the Red Hand.

Now the leadership of the Red Hand grows concerned about Idmon’s influence within their organization, while Idmon commands those loyal to him to bring him downcast sacrifices. The skinweaver believes that by consuming enough flesh of the fallen angels he will ascend to godhood. Whether he’s correct or not, Idmon and his loyalists will soon come to conflict with the Red Hand in a shadow war that threatens to drag the Ebon Syndicate, the Altenheim city guard, and many innocents into the ensuing violence.

Idmon In Your Campaign

If you wish to incorporate Idmon into your Grim Hollow campaign, consider using or drawing inspiration from the following plot seeds.

Into the Parlor. In a market, tavern, or other public place the player characters are approached by a young boy. He explains that his master, a downcast merchant, has recently disappeared. The boy fears the merchant was targeted by the Red Hand, stating that he saw figures in ornate and frightening leather armor make off with his mentor. After an investigation around Altenheim, the player characters will discover this is not the first downcast to disappear in recent times. The trail leads them into an area of the woods many locals believe is haunted or cursed.

Tangled Web. Adi Raiko, the leader of the Red Hand, suspects that Idmon will soon make an attempt on her life. To thwart this potential threat, she adopts a false persona and contacts the player characters, hoping that hiring outsiders will give her plausible deniability if the adventurers are unable to dispatch her adversary. Although she is willing to provide intelligence and pay the player characters handsomely if they are successful, she will turn against them if they reveal her role to Idmon or anyone else in the Red Hand or Ebon Syndicate.

Roleplaying Idmon

Idmon is a classic narcissist, only capable of thinking of his own wants and certain of his superiority over others. With the recent encouragement by those members of the Red Hand that have taken to worshipping him, Idmon has begun styling himself as a god. When others speak with him, he expects deference. When he deigns to talk with humanoids, he is patronizing and condescending, certain that they can’t possibly fathom the depths of his genius.

Idmon’s Traits

Ideal. “I will become the god I was always meant to be.”

Bond. “As a creature of unequaled intelligence, I deserve adoration and sacrifices.”

Flaw. “I crave the flesh of all humanoids but none so much as the downcast.”

Idmon in Combat

In combat, Idmon is arrogant and certain of his inevitable victory but still relies on underhanded tactics. If possible, he will begin a conflict by ambushing his prey, typically by dropping on them from the ceiling of his lair. Once the battle has begun, he attempts to neutralize most assailants with his abilities to restrain and frighten while cutting down those who manage to fight back.

Idmon feigns fearlessness but if his life is threatened, he would flee to save himself. He happily commands his cultists and other loyal members of the Red Hand to die fighting while he escapes.

Deep forest where Idmon keeps his lair

Artist: Titus Lunter

Idmon’s Lair

Idmon has made his lair in a hidden cave in the woods outside Altenheim. Despite his gruesome appetite, Idmon is meticulous about maintaining his home and leaves no trace of his victims. Although he has made no special efforts to cultivate their presence, several varieties of large spiders are more prevalent near his lair than elsewhere in the woods.

The challenge rating of Idmon is 9 when he’s encountered in his lair.

Lair Actions

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

  • Worshippers rush to Idmon’s aid. 1d6 cultists appear in unoccupied spaces within 60 feet of Idmon. These cultists take their turn on initiative count 1.
  • Ethereal spiders quickly form a 10-foot radius sphere web anywhere within the lair. The web is considered difficult terrain. Creatures within the web when it appears, or who move through the web on their turn, must succeed on a DC 12 Strength saving throw or be restrained until the web is destroyed or the creature breaks free. A creature restrained by the web can use its action to make a DC 12 Strength check. If it succeeds, it is no longer restrained. The web has AC 10, 20 hit points, is immune to poison and psychic damage, and vulnerable to fire and slashing damage. If the web is not destroyed sooner, it is destroyed after 10 minutes.
  • The faces of silently screaming humanoids appear across the surface of Idmon’s leather armor. All creatures within 30 feet of Idmon must succeed on a DC 13 Wisdom saving throw or be frightened until the end of their next turn.


Regional Effects

The region containing Idmon’s lair is influenced by Idmon’s aberrant nature, creating one or more of the following effects:

  • The air within 1 mile of Idmon’s lair is unusually dry. Creatures who remain within this area for more than a couple hours find their skin becomes ashy and cracked.
  • An abnormal variety of mundane spiders spin their webs within 3 miles of Idmon’s lair. Within this area giant spiders and giant wolf spiders can also be encountered with greater frequency than is usual.
  • The dense canopy of trees within 3 miles of Idmon’s lair causes little light to reach the forest floor. Within this area there is only dim light and darkness beneath the trees.


If Idmon dies, these effects fade over the course of 1d6 days.

Idmon Monster Rules




If defeated, Idmon’s ornate studded leather can be converted into three sets of +1 studded leather armor fit for Small or Medium humanoids. Doing so requires a successful DC 11 Dexterity ability check using leatherworker’s tools and 500 GP worth of fine inks. If the ability check is successful by 5 or more, +2 studded leather armor is created instead.

Idmon’s lair contains many more treasures. Within his home are +1 leatherworker’s tools and 3d12 rare books, each worth 1d6 x 10 GP. These books cover a variety of cultural, philosophical, and religious topics. Although it is of no fixed monetary value, Idmon has also written extensive notes on his dealings with the Red Hand. The book containing his notes would be of significant value to local authorities or other enemies of the Red Hand.

Idmon's scrolls and notes

Artist: Anna Verhoog

Finally, there is a 50% chance of a living humanoid being caged in Idmon’s lair at any given time. If the result of the roll is 25 or lower, the humanoid is a downcast. Otherwise, it is another humanoid race common to the Abendland region.


DC 12 Intelligence (Arcana): Skinweavers are aberrations that resemble a blend of humanoid and spider features. Their name is taken from their proclivity for slaying humanoids and turning their skins into intricate leather crafts and armor.

DC 14 Intelligence (Nature): There is a certain area in the woods outside of Altenheim cautious hunters refuse to hunt. This region isn’t marked by any signs but careful observers will note an unusual number of spider webs amongst the forest canopy.

DC 16 Intelligence (History): The Red Hand is an organization of professional killers working under the auspices of the Ebon Syndicate. Several years ago the Red Hand’s reputation became even more sinister when its agents were seen wearing the remains of their victims.


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