A Bestiary of Boss Monsters from D&D Beyond's Crooked Moon
Transcribed content from our recent YouTube video: https://www.youtube.com/watch?v=m-qBdvV9S5k
Transcription
From a flaming, headless horseman riding vengeance across cursed roads… to a ghost train that ferries souls between life and death—today we’re diving into the legendary monsters of the Crooked Moon, from D&D Beyond. These aren’t your average dungeon crawlers. These are actually campaign-defining nightmares, more akin to a bestiary of “boss monsters” that you can throw at your gaming group in this Halloween-style setting.
So, let’s talk about my favorite four that will haunt your players forever.
Welcome back to Eternity TTRPG, your lantern in the dark woods of Dungeons & Dragons adventures. Today, we’re peering into the shadows for another awesome dive into one of my favorite D&D settings of all time – Crooked Moon.
Let’s dive right in.
We’re starting strong with the Galloping Headsman—a headless executioner based, of course, on the “headless horseman” from “the Legend of Sleepy Hollow.” The twist here is that the horseman is a centaur. Still missing his head, which is now filled with gouts of fire. But in my opinion, no Halloween, or Halloween-inspired campaign, is complete without a visit from the headless horseman.
In one hand, this legendary monster wields a massive two-headed axe that can literally decapitate a player if it crits. And in the other it holds a burning pumpkin skull, shifting with agonized faces.
This monster is cinematic. Imagine a chase sequence where the Headsman’s lair warps roads themselves—stretching paths, halving travel speeds, and giving the sense to players that they can never quite escape.
His weakness? The original skull he lost. If your players find and wield it, he suddenly becomes vulnerable. Until then… run.
I love boss fights where there’s a secret that players need to uncover, to make the battle well – winnable. Until that secret is uncovered, the “boss” feels truly like something of legends and nightmares.
Number two is another top pick that I think Crooked Moon absolutely nailed: the Ghostlight Locomotive. This one is just so different from anything you typically see in D&D, or almost any roleplay game. It’s a phantom train barreling between life and death, burning souls as fuel.
Most of the time, the Ghostlight Locomotive runs its eternal route, burning souls like coal, but carrying them off to the afterlife. But that balance is fragile. When its soul-fuel becomes corrupted—whether by dark magic, a curse, or too many wicked spirits—something inside the engine snaps. Suddenly it’s no longer mindless. Instead, the train becomes aware of the countless souls it has consumed, and with that awareness comes rage. That’s when the Locomotive transforms into a nightmare on rails, lashing out at the living and dragging anything in its path down into the mist.
And speaking of, the ghostly, mile-wide shroud of mist that surrounds the train prevents players from fully healing with rest, and even magic feels weaker—potions and cure spells only work at half strength.
Consider the power of the mist itself, this legendary monster is actually part dungeon, part boss, and even part existential crisis.
At number three, we move from machines to nature gone wrong—meet the Beast of Blight. Once, this beast was Farryn of the Greenwood, a druid who turned to forbidden magic to bring back her dead lover. And that, as you might expect is where things went wrong. Instead of restoring life, her magic twisted inward. Nature didn’t heal her grief—it reflected it, warping her body with rot, fungus, and decay. In trying to preserve love, she became the embodiment of loss: a beast that spreads corruption with every step.
Now, the Beast’s lair is a cavern at the heart of a rotting forest, where decay seeps even from stones. In that place, the natural world turns against you—forests wither, food spoils, and even spells that create water only produce half their normal amount.
In this cavern, the Beast can teleport through rot, spew necrotic spores, and even she can even impale grappled creatures on her exposed ribs, holding them restrained while dealing piercing damage.
But buried inside her, a flicker of Farryn’s memory or emotion that survived the corruption, remains. Show the Beast the likeness of her lost love, and for a moment, the rot burns away and Farryn comes back through. When this happens, she takes immediate psychic damage, and she also has Disadvantage on all d20 tests until the start of her next turn – making this fight much, much easier.
Lastly, we move to the Dusk Mother. Her keening wails carry through settlements, where she searches endlessly for her lost children. Some say they died from her wrath, others say it was from her negligence.
But in truth, it doesn’t matter how [her children died]—because in her own mind, she carries all the guilt. That shame, that unbearable grief, twisted her into something more than a ghost. It made her into the Dusk Mother.
Directly from Crooked Moon: “Now she cries in shame for that loss as she searches for her children, or for souls to claim and fashion into dolls in a futile attempt to fill the void in her doomed soul.”
The Dusk Mother carries giant shears and a great tolling bell, as she wanders across the countryside. Her presence warps reality—villagers absentmindedly start humming funeral songs, while adventurers become unable to rest.
Once again, the players may have some advantage though if they ever have to face her, for if she ever sees her children’s trinkets or spirits, she collapses, overcome with guilt.
This is the kind of boss fight that is emotionally heavy. In this case, your players aren’t just fighting a legendary monster. Instead, they’re facing an avatar of grief, itself.
So that’s four of the most terrifying legendary monsters from The Crooked Moon. The Galloping Headsman, the Ghostlight Locomotive, the Beast of Blight, and the Dusk Mother. Each one is packed with lore that can fuel more than a few game sessions, and interesting mechanical twists for climactic encounters.
But now I want to hear from you—if you had to unleash just one of these horrors in your campaign, which would it be? Would you make your players ride the Ghostlight Express, or see if anyone dares face the Beast of Blight head-on?”
Drop your pick in the comments, and don’t forget to like and subscribe for more D&D news and monster spotlights. Until next time—keep your head on straight… unlike the Headsman.
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Author - Jacob Tegtman
Dear reader, I hope you enjoyed this article. Tabletop gaming has been a passion of mine since I was 6 years old. I've played just about every game from Dungeons and Dragons to video games like Final Fantasy. These games have inspired me, made me laugh, made me cry, and brought me endless hours of enjoyment.
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