A horror-themed encounter for 3rd-level parties in D&D 5E, with battle maps and monster tokens included!
This encounter is Part 3 of 3 in our series for the Eisenstein Mining Compound. Be sure to refer back to Part 1 to learn about all the different characters in the Compound, with their varied relationships and motivations. Part 2 covered the party’s entrance into the mines and their first run-in with a monster released from within.
Introductions are very important for laying an encounter’s groundwork and providing the party with the clues they will need. This is especially true for investigative encounters. The purpose of the inner chamber is to give these clues, allowing the characters to build from them once they leave and take full control of how the encounter proceeds.
Into the Central Chamber
Once the characters have dealt with the Theo-dretch, their next objective is to reach the ruin deeper in the tunnels. They will see the entrance shortly after crossing the bridge. The path that follows the minecart tracks to the left will simply lead to a dead-end shaft, while veering right will see them cross another branch of the fissure before noticing a glowing crack around another right-hand turn. This is the tunnel that breached into the ruins.
The bridge pierces back into the fissure’s wall, continuing some 20 feet further. Another tunnel branches to the left but it is the far wall that catches your attention. The rough surface marks where the miners abandoned their task, shards and rocks scattered along the ground. A crack runs the full vertical length of the end wall, no more than a foot wide at any point, and with an open space visible beyond. Both the inside of the crack and wide splatterings around it are stained in a dark, dry red. Icy turquoise light pulses within.
It is up to the characters to find their way inside. They may try to squeeze or teleport in, or they can easily find pickaxes and other tools in the previous rooms to widen the crack. The players are likely to be on edge and expecting an attack. Make use of this by giving them full control and interjecting as little as possible. Once they have made it inside, their investigation can continue.
The room inside is a cube, roughly 20 feet on each side. It is hewn of the stone around it, carved without any visible entrance or connecting pathway and with runic lines coating each of the walls. These lines emit the blue glow. Strangely, the quarter of the room around the broken wall is dark, its runes inert. They all surround a small raised section in the room’s center, which is soaked with liquid that pools on the ground around it. You notice a glint of reflected light in the closest pool. Looking down reveals a metal medallion floating in the darkened water. The air around you is crisp and stagnant, stained with the smell of blood that lingers in your mouth.
For the sake of the characters’ investigation, it is important to understand the purpose and recent history of the room.
It was created as a prison for the creatures that have now escaped. A group of mages, possibly the same ones responsible for the monster and its young progeny, took advantage of their weakness to the cold by freezing them in ice long ago. The runes adorning the walls would keep the temperature low enough for them to remain frozen and resist the heat of the caves’ thermal vents.
Unfortunately, the miners broke through the wall. This destroyed one portion of the runes, allowing the temperature to slowly climb and thaw the monsters in the time that Eisenstein was waiting for the researchers to arrive. They then broke free when they felt the group approach.
In the attack, the primary creature snuffed any light sources before snatching Gerim when the researchers turned to run. It assumed his form, while the smaller monster followed and took Theodore. The ‘Gerim’ currently resting in the Steaming Steps is, in fact, the creature.
If the characters were unable to permanently defeat the previous creature, or if it makes a reappearance, you can use this room to help them. The lit runes can fulfill the requirement of cold damage for negating its regeneration. The same can apply to leading it outside and into the snow.
DC 13 Intelligence (Investigation) check…
The air shifts as you move around the chamber, scanning over the runes and rubble. You notice that, as you step out into a quadrant with lit runes, the temperature drops dramatically, to almost as cold as the tundra outside. You step back to the dark runes and it rises again.
This should tell the characters that the broken wall disrupted whatever it is the room was fashioned to do. Combining this knowledge with the pools of water should indicate it was designed to keep something frozen. For the astute, it is also a clue to their weakness, if the characters were unable to discern it in the previous encounter.
DC 15 Intelligence (Investigation) check…
You are drawn to the far wall, where you notice additional grooves under a thick layer of dust and grime. Wiping the slick much away, you are able to uncover a disturbing, carved portrait. The relief depicts two forms of almost shapeless tendrils and teeth, one far smaller than the other. The larger seems to wrap around its partner, shielding it as a parent might protect its child.
This is the most obvious and direct indication that the Theo-dretch was not the only creature freed. It should tell the characters that there is another, more dangerous version of the monster, which they may be able to connect to the presence of Gerim’s amulet.
You can find all of our maps and packs for the Eisenstein Compound and its mines, including the broken chamber, below…
Intruder in Eisenstein
Once the party has investigated the room to the best of their ability and discerned that the creature is no longer present, they can make their way back to the Eisenstein Compound. Leaving the mine will be uneventful and give them time to discuss what they know. This also helps to tell you what they have and have not figured out, which will be important for the coming investigation.
By the time the characters make it outside, the area will have been covered in a thick snowstorm. It will not prevent them from returning to the compound but it does have the following effects:
- Any area within the storm is considered difficult terrain.
- Vision is greatly reduced within the storm. Creatures can only see and hear clearly within a 5-foot radius of themselves and have disadvantage on Wisdom (Perception) checks that rely on sight or hearing to detect anything beyond this radius. Anything more than 15 feet away is heavily obscured.
The party will be prompted to return to the Steaming Steps, where Emil is speaking with Yorick. Once they do, Pelion will rush to them. He will explain that Gerim arose when the storm began and walked out, disappearing into the white, and will beg the characters to follow and find him before he succumbs to exposure. Pelion will point them in the direction that Gerim was headed, out of the compound.
Following this heading will take the party down a slope and to the side of a hot spring, where Gerim’s body has collapsed into the water.
At the base of the slope is a small group of pools, their steam being buffeted by the storm. You immediately see that one of them is almost blackened with blood. A lifeless form is pressed into the mud. Grey and blue robes are barely visible amongst the damage, torn open from the back.
A simple investigation will find that the ravaged body does not bear a medallion, confirming it to be Gerim. The wound is from the creature’s exit through his back.
DC 13 Wisdom (Survival) check…
A path of heavy boot prints leads away from the body. They quickly vanish beneath the storm’s snowfall, though one thing is clear: they were headed back to Eisenstein.
Everything that happens beyond this point is up to the players. They are in control of finding and defeating the creature before it can take more victims. This makes it impossible to perfectly predict how events will proceed. Instead, here are some important details and explanations to keep in mind as the creature and the party work against each other:
- The creature is effectively a parasite, taking control of its victim’s form. When it does so, it is visibly indistinguishable from them. It also gains their memories of the previous month and is able to mimic their personality. The creature also gains its host’s abilities, including (but not necessarily limited to) racial abilities, proficiencies, and spellcasting.
- The creature seeks warmth. It is vulnerable to the cold and requires heat to remain active. New victims provide this warmth for up to 12 hours, depending on the environment, after which it will become desperate to move on. The hot springs and forges within the refineries can also provide heat.
- The creature is also intelligent. It is able to plan its actions and scheme against those that are hunting it. This might include framing other residents, killing without assuming the victim’s form, or even aiding the investigation to endear itself to the party.
- Each character will react differently. Emil Eisenstein will become paranoid, sealing himself and the Alabors within the Eisenstein Manor and denying anyone else entry. Riza Alabor will seek to protect her family, though Kurtis will object to being locked in a house. Use each character’s description to determine their actions as tensions rise. There are also a number of miners and workers within the compound with which to expand your roster.
With these in mind, it is a matter of tracking who has what information and using that to create a tense investigation for the party. Accurate note-keeping is your best friend. This allows you to carefully track the many secrets being kept, which can be the best way to create tension and intrigue. As the characters are the only ones to know the truth, it is initially up to them to decide who they tell. Though, what happens if someone else finds out and begins to question the secret that these strange adventurers were keeping?
Have the creature act tactically and use any trick it can. And remember that it will only reveal itself if left with absolutely no other choice.
Of course, it’s only a matter of time until one of our named characters becomes the creature’s victim. And we have tokens for just that! Thanks to David Wilson, we have a terrifying trio of mutated tokens, ready to lash out with tendrils and teeth.
If you think you might end up lacking in ideas or a next step for the creature to take, or if the characters may hit a dead end, you can prepare specific events that will reignite the encounter. You can come up with your own or use the following examples:
- The creature, while in the form of someone other than Emil or an Alabor, will claim a victim. It can then transport the body into the Eisenstein Manor’s yard and leave it in the springs, causing blood to very obviously flow down into the pools below. This will draw attention to the Manor and create suspicion. Meanwhile, Emil will frantically seek to hide what happened in an attempt to deflect the suspicion, likely making himself and those around him even more suspect in the process.
- During the night and after taking a new form, the creature will use its previous body to frame a party member. It can do this by tossing the body into their room as they sleep. This will create enough noise to draw attention and bring Yorick, Pelion, and others to the room, while the creature slinks away. Whoever is in the room will also wake up. Depending on their reaction, they may incriminate themselves further, which a well-disguised creature can take advantage of. If they do not, the action is still an effective message to its enemies.
- Attacking one or more of the miners, or even simply exposing the situation, can send the entire workforce into an angered panic. This will create conflict between them, Emil, and Marco. Workers gathering at the Manor’s gates not only draws attention away from the creature and makes it harder for the party to operate, but could also provide the creature with an opportunity to breach the Manor. Taking the form of one of Emil’s guards could then give it the opportunity to manipulate the owner without needing to control him directly.
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