The Dome of the Phoenix

I ran the following adventure for two different groups during our recent gaming weekend. While both groups fared fairly well, only one was able to find the treasure at the heart of the Dome of the Phoenix.

The Dome of the Phoenix is a short 5e dungeon crawl for 4–5 3rd-level characters, designed to emulate a classic megadungeon delve. The Dome could easily be run as a standalone adventure, or inserted as a sublevel into an established megadungeon.

Background

A fresco of a Phoenix from the Great Dungeon.

The Dome of the Phoenix is a legendary area on the third level of the Great Dungeon of the North, consisting of the Dome itself and several surrounding rooms and chambers. First discovered some 35 years ago, the Dome soon became famed for the hauls of rubies that were brought out of it. The Dome was said to contain a fabulous treasure vault that could not be accessed by adventurers.

As sometimes happens in the Great Dungeon, the Dome would mysteriously disappear and reappear from time to time. Nearly seven years have passed since adventurers were last able to access the Dome.

Two weeks ago, a party of dungeoneers led by the human fighter Hodge Thorntown rediscovered the entrance to the Dome. Hodge’s party, the Hodgepodge, consisted of the adventurers Brother Waylen, Idril Silvertree, and Piers Redmane. For an expedition to the Dome they hired several henchmen to round out their numbers: Liam, Brother Rory, Sothye the Amazon, and Alyna.

The party ran into a hobgoblin ambush: Liam was killed immediately and Sothe the Amazon fell while acting as rear guard. The party regrouped and drove the hobgoblins back, but Brother Waylen was killed in the ensuing fight. Hodge insisted the expedition press on.

Hodge, while taking point, was murdered by a doppelganger and secretly replaced. The group then encountered a troll that tore through the remaining members of the Hodgepodge. Piers Redmane was killed and his magic elvish longbow lost. The decimated group was forced to withdraw from the Dungeon.

Upon returning to Delvetown Ildril Silvertree shunned Hodge, blaming him for the death of her beloved Piers. Along with Rory and Alyna she returned to the Dungeon, vowing revenge. The doppelganger masquerading as Hodge has been hanging around Delvetown, looking to return. If approached it will gladly guide a fresh party of adventurers into the depths of the Dungeon.

Rumors

Characters spending time in Delvetown can easily pick up most details of the Hodgepodge’s doomed expedition, except for Hodge’s replacement by a doppelganger. Additional effort can turn up several rumors about the Dome:

1. The Dome of the Phoenix is populated by fire monsters.
2. Ghouls and other undead have overrun the Dome.
3. A magic sword lies at the heart of the Dome.
4. The Dome is riddled with secret and hidden passages.
5. Adventurers of yore brought a cache of rubies worth a king’s ransom out of the Dome.
6. A young red dragon lurks at the heart of the Dome.
7. Hobgoblins of the Long Death tribe are systematically ransacking the Dome.
8. A shrine to an archdevil is hidden somewhere in the Dome.

Dungeon Key

This map was created using the incredibly awesome Dungeon Scrawl tool.

Each square is equal to ten feet. Unless otherwise noted, all corridors in the Dome complex are 10 feet wide with arched ceilings peaking at 15 feet high. Room ceilings are 16 feet high and chamber ceilings are nearly 20 feet high. Doors are made of stout oak bound in corroded iron. All areas are dark unless otherwise noted

Wandering Monsters

Check every 1d4 turns, wandering monsters occur on a 1 on 1d6.

1. 1d2+3 Hobgoblins
2. 1d2+1 Ghouls
3. 1 Doppelganger
4. 1 Gelatinous Cube
5. 1d2 Gricks
6. 1d2 Cyclopes

Entrance

E. The Phoenix Room

This octagonal entrance room has doors on the east and west walls. On the north wall is a statue of a phoenix in its nest, its head pointing east. A DC 15 Wisdom (Perception) check will indicate the presence of a secret door behind the statue. A DC 15 Intelligence (Investigate) check will discover the opening mechanism: Turning the head to the west causes the statue to slide aside, revealing a passage to the north.

The Eastern Section

A1. Chamber

A DC 10 Wisdom (Survival) check indicates recent activity in this area. A DC 15 Wisdom (Perception) check will find markings carved into the lintels of the two exits. A DC 10 Intelligence check reveals these are hobgoblin signs, while a DC 15 or better will indicate the northern exit is a warning and the southern exit is marked as clear.

A2. Stairs

A great quantity of dried blood and three broken spears are at the top of the stairs. A DC 15 Wisdom (Survival) check indicates the blood is less than a week old. At the bottom of the stairs are two broken polearms and more blood. The weapons have wickedly curved and hooked blades, and a DC 15 Intelligence check indicates they are of hobgoblin manufacture. An elf makes this check with advantage.

A3. Owlbear Room

The door to this room is nailed shut from the outside. A DC 20 Wisdom (Perception) check will reveal growling on the other side. Inside are the mangled corpses of three hobgoblins and one very angry and hungry owlbear.

A4. Chamber

The eastern wall of this large, irregular chamber is painted in what was once a vibrant mural of a phoenix emerging from a fire, though the features are grimed and hard to make out. Rude goblin words have recently been scrawled on the mural. The phoenix’s beak points toward a secret door in the eastern wall, which can be located with a successful DC 15 check.

A5. Alcove

The corpses of Liam and Sothye the Amazon lie here, with the words “ELF FRIENDS” scrawled on the far wall. Ildril Silvertree will pay 100 gp for the recovery of both bodies. If characters spend any time investigating this area, three hobgoblins from A6 will charge down the hall, roaring in fury while the fourth alerts the other hobgoblins in A8.

It will take 3 rounds for the reinforcement hobgoblins from A8 to take up positions in A6, from which they will fire arrows down the corridor.

A6. Chamber

Four hobgoblins of the Long Death tribe are on guard in this vaulted chamber. One watches the corridor to the west, while one stands in front of the door to A8. A sergeant has a small locked coffer with 12 cp in it. He carries the key on his belt.

A7. Offal Room

The floor of this room is sunken three feet below the corridor, but filled with offal. Moving through this room is difficult terrain. An otyugh lives here. It has reached an accord with the hobgoblins, who happiy bring their refuse here as tribute.

A8. Guard Room

Five off-duty hobgoblins are in here along with bedrolls and provisions. They have scrawled rude words on the walls and crude pictures of elf torture and degradation. The hobgoblins collectively have 11 gp.

A9. Pool Room

The center of the room is dominated by a 10-foot wide pool of blue, gently-swirling water roughly 3-feet deep. The pool radiates conjuration magic. The water is drinkable, and any creature standing in the pool must make a DC 13 Wisdom save or be teleported back to Delvetown.

A10. Troll Room

This room is occupied by a hateful troll. The floor is littered with bones picked clean and the corpse of Piers Redmane with his elvish blade, a +1 longbow. Ildril Silvertree will pay 500 gp for the recovery of his body. Scattered among the bones are 30 ep, 1,900 cp, and one red spinel worth 100 gp.

A secret door in the north wall can be found with a DC 20 check.

The Western Section

B1. Chamber of Frogs

This vaulted chamber is damp and the floors are slippery. Half a dozen small, pale frogs croak and hop around here. They will approach any characters without fear, but will recede quickly if harmed or harassed in any way. If allowed they will follow the characters through the dungeon. Dexterity (Stealth) checks made with a frog retinue are with disadvantage, while Widsom (Perception) checks are made with advantage.

B2. Guard Room

The southern approach to this room is littered with the corpses of several squashed frogs. Inside are the servants of the night hag Pericha in B6: the ogre Ned and his half-ogre son Jago. Ned has 12 gp in a pouch on his belt.

B3. Refuge

This room is poorly lit by several torches. Four thugs have holed up in this room after running into Ned and Jago at B2. A dead fifth thug is on the floor, his wounds crudely tended. The thugs, named Jor, Grab, Wal, and Dag, will pretend to be adventurers and will offer to join with the characters. They are actually chaotic evil brigands, members of the Reaper faction, and will betray the party at the first opportunity. Jor has 6 gp, while Grab has 3 gp and Wal has 1 gp.

B4. Room

This room is empty. A small leather pouch with 10 sp is hidden under a flagstone in the northwest corner, and is discoverable with a DC 20 Wisdom (Perception) check.

B5. Fountain Chamber

At the center of this room is a circular fountain, 15 feet wide with the statue of a jovial, 8-foot tall black frog, its front arms raised toward the ceiling as if in celebration. Water gushes out of its mouth and cascades into the pool at its feet. The entire fountain radiates transmutation magic. Any living creature touching the water must make a DC 12 Constitution save or be polymorphed into one of the small, pale frogs. Creatures drinking the water make this save at disadvantage.

B6. Home of the Hag

The door to this room is hung with a cheery cross-stitch sampler with the following message in neat Common: “Enter, weary, and find your rest.”

The room within is furnished like a cozy hut with table, place settings, a bed, and several chairs. Inside is the night hag Pericha, polymorphed into the form of a kindly old woman. She will invite the characters in but is so vile and impatient she will not be able to maintain the ruse for very long before attacking the characters.

Pericha has six small rubies worth 500 gp each in a green glass decorative bowl shaped like a large scallop shell.

The Secret Chambers

C1. Bone Room

This dusty, cobwebbed room is littered with broken and gnawed bones, bits of broken weapon and armor, all very old. 13 cp can be found amongst the bones.

C2. Corpse Room

Several desiccated corpses, covered in dust and cobwebs, lie in this room. A DC 10 Intelligence (History) check indicates that their clothes and gear are several decades old.

C3. Guard Room

Seven zombies sit on the floor of this room, covered in dust and mold. When the door opens tiny pinpoints of light glimmer in their eyesockets and they rise to attack. 22 cp are found on their moldy bodies.

C4. Pit Trap

From C3 a corridor runs north twenty feet before turning east and ending in a door. A hidden pit lies at the turn, its cover the same stone material as the corridor floor. A successful DC 15 Wisdom (Perception) check discerns an absence of foot traffic over the section of floor that forms the pit’s cover. A successful DC 15 Intelligence (Investigation) check is necessary to confirm that the trapped section of floor is actually the cover of a pit. The door around the corner is actually a false door at the end of a dead end.

When a creature steps on the cover, it swings open like a trapdoor, causing the intruder to spill into the 15-foot pit below. A creature falling into the pit takes 5 (1d10) bludgeoning damage plus 11 (2d10) piercing damage from the spikes. After a creature falls into the pit, the cover snaps shut to trap its victim inside. A successful DC 20 Strength check is necessary to pry the cover open. The cover can also be smashed open. A character in the pit can also attempt to disable the spring mechanism from the inside with a DC 15 Dexterity check using thieves’ tools, provided that the mechanism can be reached and the character can see.

A corpse impaled on the spikes has 11 gp. From the bottom of the pit passages run west to C6 and north to C7.

C5. Charnel Room

This dusty room reeks faintly of death and decay.

C6. Landing Room

Three ravenous ghouls lurk at the bottom of the stairs, waiting for any living creature to either come from C5 or the pit trap at C4. There is 22 cp scattered on the floor around them.

The Hulking Ghoul waits for living creatures to approach.

C7. Secret Door

A dingy mural of a phoenix is painted on the north wall of this intersection. The mural is covered with cobwebs and is spotted with a DC 10 Wisdom (Perception) check. The wall on which the mural lies is a secret door, discoverable with a DC 15 check.

C8. Chamber of the Hulking Ghoul

A hulking ghoul waits here for living creatures to enter. The chamber is filled with smashed and broken bones.

Hulking Ghoul

Large undead, chaotic evil
Armor Class 14 (natural armor)
Hit Points 75 (10d10 + 20)
Speed 30 ft.
Str	Dex	Con	Int	Wis	Cha
18 (+4)	14 (+2)	14 (+2)	9 (-1)	12 (+1)	8 (-1)
Damage Immunities Necrotic, Poison
Condition Immunities Charmed, Exhaustion, Frightened, Paralyzed, Poisoned
Senses darkvision 60 ft., passive Perception 11
Languages Abyssal, Common
Challenge 4 (1,100 XP)
Keen Smell. The hulking ghoul has advantage on Wisdom (Perception) checks that rely on smell.
Regeneration. The hulking ghoul regains 10 hit points at the start of its turn if it has at least 1 hit point. The trait doesn’t function if the hulking ghoul takes fire or radiant damage.
Stench. Any living creature that starts its turn within 5 feet of the hulking ghoul must succeed on a DC 13 Constitution saving throw or be poisoned until the start of the next turn. On a successful saving throw, the creature is immune to the stench for 1 hour.
Turn Defiance. The hulking ghoul and any ghouls or ghasts within 30 feet of it have advantage on saving throws against effects that turn undead.
Undead Nature. A hulking ghoul doesn’t require air, food, drink, or sleep.
Actions
Multiattack. The hulking ghoul makes two melee attacks.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 17 (3d8 + 4) piercing damage.
Claws. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 14 (3d6 + 4) slashing damage. If the target is a living creature, it must succeed on a DC 13 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

C9. Bodak Lair

This chamber and the corridor approaching it is freezing cold, filling living creatures with a noticeable sense of dread. One bodak (Volo’s Guide to Monsters) is found here.

Around the room are piles of treasure: 110 pp, 1,300 gp, 5,000 sp, and 700 cp; six 100 gp red garnet gemstones, and a Potion of Greater Healing.

The Inner Sanctum

The Thing in the Well guards the Dome.

D1. Chamber of the Shaft

This chamber is dominated by a 15-foot wide opening in the center of the room, which plunges down 15 feet. At the bottom of the shaft is a black pudding. A passage runs north from the bottom of the shaft to D2.

D2. The Well

This chamber has only 15-foot wide stone well filled with dark, foul water. Just under the water’s surface lurks the Thing in the Well, a horrible mass of writhing, spiked tentacles. The Thing will attack anyone trying to cross the room.

The Thing in the Well

Huge aberration, unaligned
Armor Class 15 (natural armor)
Hit Points 105 (10d12 + 40)
Speed 20 ft., climb 20 ft., swim 30 ft.
Str	Dex	Con	Int	Wis	Cha
18 (+4)	13 (+1)	19 (+4)	1 (-5)	11 (+0)	9 (-1)
Saving Throws Con +7
Senses blindsight 30 ft., passive Perception 10
Languages —
Challenge 6 (2,300 XP)
Amphibious. The Thing can breathe air and water.
Actions
Multiattack. The Thing makes three tentacle attacks.
Tentacle. Melee Weapon Attack: +7 to hit, reach 15 ft., one target. Hit: 8 (1d8 + 4) bludgeoning damage plus 4 (1d8) piercing damage. If the target is Large or smaller, it is grappled (escape DC 14) and restrained until the grapple ends. The Thing has five tentacle, each of which can grapple one target.

The well is 20 feet deep, and at the bottom lies a corpse with a small rotten sack containing 3 red spinels worth 100 gp each.

D3. The Dome of the Phoenix

This square chamber contains an ever-burning brazier in the center. Two locked bronze doors are in the west wall. They are immune to physical harm and cannot be picked or opened by any magic less than a wish or miracle. The ceiling is a painted dome depicting a phoenix emerging from a fire, soaring over landscapes, and then consuming itself in a pyre. Within the painting is a concealed message written in Common, discovered on a DC 10 Wisdom (Perception) check:

A stone of red
Into fires fed
Opens the way

Placing a ruby or other red gemstone worth at least 10 gp in the fire opens both doors to D4. Placing anything else summons a fire elemental that attacks the characters.

D4. The Sword of the Phoenix

Inside this small room is a small altar on which sits two small rubies worth 500 gp each and the Sword of the Phoenix, a flame tongue longsword. Command word: chol.

Attributions

The image of the Phoenix Fresco was generated using DALL-E2. The dungeon map was created using Dungeon Scrawl. The Hulking Ghoul miniature is a Games Workshop Crypt Horror. The Thing in the Well miniature is from the Reaper Bones 5: Escape from Pizza Dungeon Kickstarter.