The Dungeon of the Fire Opal as it is called here, is a restocking/reimagining of the original sample dungeon from the 1st edition AD&D Dungeon Masters Guide. I used to stare at that section of the 1e DMG and mentally try to stock the rest of the dungeon. Only the first few rooms were described since it was being given as an example of play.
With the launch of 3rd edition D&D they revisited the dungeon map, fully stocking it and giving it a background story, that of the ruin of a monastery once run by evil monks who had a great treasure in the form of a fist shaped fire opal reputed to have magic power.
Since I'm going through issues of Dungeon Magazine looking for adventures to link to a Ptolus campaign, I thought it might be fun to once again take this classic map and restock it to represent a section of Ghul's Labyrinth beneath the city.
Occasionally it might be interesting to reskin and modify a monster, and to make new traps and events to experience.
So let's get started: If you need a quest giver to send the party on their way consider Wynn Rabinall, leader of the Order of the Fist. He has received word that a magic item in the form of a fist shaped fire opal may be in this area of the dungeons. He has asked the group to check out the rumor.
Unless otherwise stated, all areas are unlit.
Unless otherwise stated ceiling height is 10 feet.
All secret doors require a DC14 or better perception to spot.
All areas other than 0, 1, and 3 are grey stone.
If you choose to include random encounters here are some suggested creatures for areas 1 through 13: All of these are from the 5e Monster Manual beginning with page 323; Giant Centipede, Giant Fire Beetle, Phase Spider, Swarm of Insects, Bandits. Roll a d8 for encounters and on results 7 & 8 use these two events: 7 - a soft hum can be heard with no discernable direction, 8 - a mild vibration can be sensed through the soles of the feet.
Area 0: Beyond the shattered remains of what was once a glass and bronze door is a polished pale green set of steps leading ahead and downward 30 feet.
Area 1: The pale green stone here matches that of the stairway, smooth and polished, appearing almost as if it is a single piece. The scent of ash from a recent fire meets your nose.
A - In the center of the room is a pile of ash and charcoal from where someone recently lit a fire. Around the remains of the fire are sooty footprints leading back toward the stairs. On the ceiling directly above where the fire had been is a soot stain.
B - In the corner is a pile of torn cloth. Investigating the scraps of cloth reveal by their smell that they once held bits of hard cheese and jerky.
C - Down this short hallway is a stout wooden door slightly ajar. The sound of running water can be heard from beyond the portal.
Area 2: The door opens into a cave chamber with a ceiling height of 15feet. There is a stream running through it with a wider pool toward the far end. Laying face down near the center of the room is a plate armor clad body with its head submerged in the pool. It is wearing a sword in its sheath and has a backpack still strapped on. In the pool can be seen small white fish lacking eyes. The fast flowing stream is clean and fresh.
Encounter - The body is a mimic that took this form when it detected noise in area 1. It will attack if disturbed. 5e Monster Manual page 220.
Area 3: The ceiling here is 30 feet high. The walls here are of a sickly yellow colored stone. Along the east and west walls are a total of 6 semi-transparent glass and steel cylinders, 12 feet tall and 5 feet in diameter. Four of them are filled with a greyish liquid and large shadowy forms can be seen floating inside. Two along the east wall are broken, the liquid spilled across the floor. There is a strange wet form laying on the floor half out of one of the broken cylinders. The creature is a log mass of hair with a bulbous head. Protruding from what passes for eye sockets are nests of fine metal wires.
A - Creatures crossing the threshold into this chamber must make a DC12 Charisma saving throw. Success results in a tingling sensation along their arms and back. Creatures failing the roll also suffer 1d6 Psychic damage and have the poisoned condition for 1 minute. Additional saves may be made at the end of the creature's turn to end the condition. Creatures succeeding on the saving throw or for whom the condition ends are immune to the effect for 24 hours.
B - Metal scaffolding is erected along the south wall reaching to a height of 20 feet. The center 30 feet of wall beginning 10 feet above the floor are covered with large steel panels. The center section of steel panels conceals a wide secret door.
Areas 4 & 5: Stored here are basic supplies including lengths of rope, leather sacks, iron spikes, lamp oit, shovels, pick axes, hammers, and the like. The rooms have obviously been explored and several crates have been opened. Hidden in the secret crawl space (3 foot by 3 foot) between rooms 4 & 5 is a small chest containing 134 copper pieces, 76 silver pieces, 13 gold pieces, and 3 small pieces of jade worth 25 gold each. The chest is locked and protected by a poison needle trap, DC15 perception check to detect. DC 13 Dexterity saving throw to avoid. Failure results in 2d10 poison damage and the poisoned condition for 1 hour.
Area 6: Immediately inside the door is a pit trap, 10 feet deep requiring a DC13 Dexterity check to avoid. The mechanism for disarming the trap and leaving the floor in place is to open the door outward. A well preserved human body lies at the bottom of the pit. If investigated it has a short sword, dagger, leather armor, and a potion of healing.
The surfaces of this room are coated in a thin rime of frost. The temperature is slightly below freezing. The walls are lined with metal shelves holding small crates of food stuffs including raw meat. Spaced every 10 feet on the ceiling are 1 foot by 1 foot metal boxes. These boxes cause 1d4 cold damage if touched. Breaking one open (Strength check DC 20 or 10 points of damage from blunt weapons) releases Brown Mold. 5e Dungeon Masters Guide page 105.
For every 1 minute of time spent in the room using a lit torch, the temperature drops 10 degrees. After a 30 degree and greater reduction, creatures are required to make a DC12 Constitution check. Failure results in 1d4 cold damage. When the temperature is reduced by 60 degrees or greater, another saving throw is required to avoid further cold damage and a level of exhaustion. These checks continue for every minute spent at these lower temperatures.