Halloween Themed Adventures

‘Tis the season to be spooky! What sort of Halloween themed dungeons, encounters or story arcs have you run or participated in in the past, or have planned for this Halloween? I expect my players to clear Wave Echo Cave next session, and afterwards they will be traveling through the Underdark to find the next dungeon. I’m thinking of doing some kind of Alien: Isolation style escape scenario where the evil NPC I expect them to take captive will get picked off first. Has anyone ever run an escape scenario in D&D and have any suggestions of how to make it interesting?

I’m also a big fan of Creepypastas and SCP, so I’ll be digging through those stories for ideas.

Possible option for the monster: the Chain Devil. It lurks in the Underdark and imprisons any humanoid it comes across. The players are corralled by the clinking of chains in the tunnels behind them toward the devil’s dungeon, where they come across its past victims. All of them are dead and decayed, but their spirits still linger and whisper a warning in the form of a creepy song.

I am running one right now. We started back on the 9th of September. I've wanted to run this Halloween adventure for a few years now, but have never gotten the chance. I am not sure if my players check this website or not, so I won't reveal it as I want it to be a bit of a surprise. On October 28th (or next session), it should be the final session of this adventure. I'll give a recap of it and make the reveal. I hope the players will get enjoyment from it as much as I am. The wait is killing me, though.

I've thought of several Halloween one-shots but haven't completed any enough to play them.
- Freddy Kreuger / Jason / whoever (not-normally killable and very sneaky killer) chases PCs around
- Casper the Friendly Ghost's uncles (from the movie) pester the PCs
- Darth Maul is stalking you, not subtly. Out of D&D, this could be the Terminator
- Some old foe they defeated but did not kill dead comes back for a swipe at revenge
- Passing a known 'haunted house', the haunts come out to investigate the passersby
- Scene based on local folklore: a curving slanted tunnel appears to be longer when going through in one direction; you could get lost. Add "a train in the tunnel" for more fun
- After hearing a local 'scary story' (about Lovers' Leap?) the PCs encounter a ghost / other undead in about that location
- Vampire-related beasties are spreading into town. There may / may not really be a vampire at the heart of this
- Frankenstein's Monster begins wandering the land. He's from the book, not the movies.

Here's a Halloween scenario I wrote and posted on enworld: The Laboratory Tomb of Dr. Viktor Vampenstein.

I'm currently writing one now called "Terror at Star Lake" which is 1st- and 2nd-level "Friday the 13th" one-shot. The PCs are sent to investigate an abandoned lodge on a lake once used by adventurers only to find that something went horribly wrong there 100 years ago this very night.

Unfortunately one of my players was out of town last week so the timing is going to be off, but I have decided to run with the Chain Devil idea in about two weeks time. I’m thinking of running essentially a mini-session of Dread. My players will clear Wave Echo Cave next session and learn that a heavily armed warship is nearly completed construction that will sail up the river to assault Crossroads where a meeting of dignitaries from every corner of the kingdom is convening. Pressed for time, they will be forced to use a Skaven built cargo transport mechanism that will take them straight to the harbor. In transit, the enclosed transport will be attacked by animated chains, ripping it apart and scattering the party underwater. It’s at this point that I’ll have them pull from the tower and the game really begins.

They will wash up in an underground riverbed, where they will find Skeeter, the Skaven slave rat they befriended a few weeks back, is now missing. Cranberry will of course freak out and insist they find him, and instead of skill checks I’ll have them start pulling from the tower. Eventually they will start hearing chains rattling in the darkness, and they will be corralled to a dungeon where Skeeter is being held. Once there, the song will play and the door will slam shut behind them, with the Chain Devil finally revealed. It will animate the chains in the room, which by themselves should amount to CR 1 creatures and a Hard encounter for five 5th level characters. While the fight is happening, the Devil will use its Unnerving Mask reaction to torment the players, in particular Tortuga who has revealed to me in a previous session that he had to kill his brother in order to escape the slave fighting pits he was raised in. Once the chains are defeated, the Devil will open the gate to engage them itself, but they will be able to try and escape out a different exit with a successful pull from the tower.

I don’t intend this to be lethal for anyone in the party, but their mascot’s life is definitely in jeopardy. I also want to have some long term debuff for anyone who topples the tower to have to bear through the next dungeon. Maybe exhaustion or something. I will have the lights off and a candle or two set around the tower when my players arrive. This should be a fun test of my DM chops in building suspense and tone setting.

Nifty mood-building gadget: small boat which is rowed by 4 skeletons. Carries the PC party across a lake or swamp or river (or River Styx). Whoever owns the boat also owns an amulet to control the skeletons.
A larger boat (keelboat size?) may have a covered room that goes all the way across the boat, with the oars sticking out as usual but no doors to get into it.

The Dungeon Master's Guild has some relatively cheap adventures available for Halloween, including a few Pay What you Want that might be worth downloading for free to see if they fit your needs:

https://www.dmsguild.com/browse.php?keywords=halloween

If the freebies do work for you, you can go back later and "buy" them again to throw some pennies at the author.

So I just finished my Halloween storyline yesterday (Oct 28), and made the final reveal. Each week since September 9th, I have ran my players through this adventure. They were tasked with helping find some missing people in a small village that sprang up around a pumpkin farm. They fought animated pumpkin monsters, a few people who were possessed/mind controlled thanks to magical pumpkins placed on their head, and finally some zombies and the big bad. The last 3 sessions had been at the pumpkin farm of the big bad. The missing people were sacrificed to help bring an evil pumpkin spirit into the material world. The PCs managed to stop this from happening.

My players defeated Linus van Pelt from summoning the Great Pumpkin. Their contact who tasked them with the rescue was Lucy van Pelt, and the missing people were Schroeder, Sally, Marcy, Peppermint Patty, and Charlie Brown (along with Snoopy and Woodstock). All the missing people (except Sally) were killed and turned into zombies thanks to some magical pumpkins embedded into their chests. Sally stood by her man, even when he killed her brother (Charlie Brown). The PCs even fought Linus's security blanket, which was made into a rug of smothering animated object.

Of course, I changed the names so the players wouldn't know right off the bat what was happening. Linus became Leineverr Peltz, Lucy was Lohnzei Peltz, and Sally was Solskeena. Zombie Charlie Brown managed to speak the name of Snoopy when the PCs kill Snoopy, who was named Snjor. Sally and Charlie were dwarves, which are based on Icelandic language, so Snoopy was named Snow, and the j is pronounced with a y sound. Also, Linus and Lucy were elves, which are german, so I went with German-sounding names for them. They seemed to have fun and got a good laugh at the reveal at the end.