You have put off planning your Halloween one-shot because you have several other goblins to skewer. We understand. And the old Kobold Press blog has you covered, friend.
You could do werewolves and vampires again. OR . . . try one of these seven top monsters, across a range of CRs, for your Halloween one-shot! Each one is a nasty critter, trick, or treat, all sourced from the newly revised and updated Tome of Beasts 1.
Bucca, CR 1/2 (Fey)
These tiny, devious faeries are also called “snatchers” because they delight in stealing from miners and hoard precious minerals and gems. They also get along with and train to ride bats. Change miner to minor and you have the makings of a trick-or-treat mystery! Send low-level characters looking for the perpetrators of stolen candy and cruel tricks with buccas as the culprits.
Citrullus, CR 3 (Plant)
Feed me Seymour! Citrullus are carnivorous plants that mimic the look of ordinary melons. But for the season, why not make citrulluses that mimic pumpkins? With a maniacal cackle, a scorned farmer reveals his “pumpkin” sale to be a devious revenge plot against those who denied him his blue ribbon at the harvest fair. Now, the PCs must rush around the countryside to save the farmer’s targets from the carnivorous gourds they brought home!
Skitterhaunt, CR 4 (Ooze)
You might not get the immediate impression from Bryan Syme’s creepy crawly artwork of this beast, but the skitterhaunt is actually an ooze that takes over giant insects! Use this magic item to get under your players’ skins. If you can’t beat them, join them!
Armor (Half-Plate), Rare (Requires Attunement)
Green ooze pulsates around the cracks of this giant insect carapace fashioned in a suit of armor. While you are attuned to this armor you gain resistance to acid damage.
Ooze Cushion. Once per short rest you can spend a bonus action to agitate the ooze that lines the interior of this shell. When you do so, treat all damage you take until the beginning of your next turn as acid damage. After the beginning of your next turn you cannot benefit from the AC granted by this armor until you take a short rest.
Cursed. There is a 50% chance this item is cursed. When it is cursed, it demonstrates a parasitic nature with a mean self-preservation streak. While wearing a suit of cursed skittershell armor, you must make a DC 14 CHA save at the beginning of every encounter perceived as dangerous. On a failure you take 5 (1d10) acid damage and are prohibited from using Attack or Cast a Spell actions until you are safely away from the perceived danger. On a success, you take only half damage and can act of your own free will.
Dream Eater, CR 5 (Fiend)
Dream eaters are drawn to sin like moths to a flame, craving the hopes and aspirations of those who live without temperance. If you want to shake things up, give the dream eater this action, replacing their normal Waking Dreams action.
New Action. Devour Aspirations (1/day). Every creature within 20 feet of the dream eater must make a DC 16 CHA save. Targets have disadvantage on the save if they committed an act of gluttony, greed, or lust in the last 24 hours. Those that fail replace any flaws they have with “Indulging my desires is the only way to achieve my dreams” and take 22 (4d10) psychic damage. The dream eater then gets 5 temporary HP for every creature affected and advantage on their next attack, save, or skill check if three or creatures were affected.
Ghost Knight, CR 7 (Undead)
Ghost knights continue to follow their creeds even after death and defeat. If you want to play up a ghost knight on an unholy crusade, you might substitute out the Necrotic Weapons trait for this one:
Spectral Crusade. When the ghost knight hits a target with its lance, both the target and the ghost knight are made incorporeal (but not the mount) until the end of the ghost knight’s next turn. The ghost knight has advantage on any creature that is incorporeal.
Fear Smith, CR 10 (Fey)
The fear smith looks like a creature out of a Guillermo del Toro movie with a tooth-filled maw for a face and courtly attire. The fear smith (also known as fiarsídhe) often wears a mask . . . and now, so can you.
MASK OF THE FIARSÍDHE
Wondrous Item, Rare (Requires Attunement)
This alabaster mask depicts a handsome elven face with painted lips and ears that point downward. While attuned to this mask you gain 15 temporary HP whenever a creature within 30 feet suffers the frightened condition. In addition, you can cast the fear spell once until you finish a long rest.
Cursed. There is a 50% chance this item is cursed. When it is cursed, the wielder takes on an icy, unapproachable demeanor and must make a DC 15 CON save at the beginning of every encounter or be blinded for 1 minute.
Cambium, CR 14 (Fiend)
A cambium prowls in voluminous robes to hide its upsetting form. It’s an ideal fit in a masquerade. Its motive is to harvest the four humours from the sickly with the intent to create serums for itself and for sale in infernal marketplaces. This creature begs for center stage in a gaslight, race-against-time medical mystery.
Start your players off with the investigation of three extremely sick NPCs, requiring medical examinations, intuitive deductions, and the connecting of clues and commonalities to find the cause—the cambium—and its final target, an ill NPC (or PC infected during the investigation?) with the last humor.
With the well being of four characters on the line, can your players act to stop this fiend before it gets what it wants?