Skip to content
CharGen Icon
CreatePricing
Take the Oath Before the Vault Breaks - AI-generated fantasy Encounter

Take the Oath Before the Vault Breaks

Encounters
Retrieve · High · 6 players, level 17

Take the Oath Before the Vault Breaks

The oath is the only surviving record of the Concordat’s hidden clause.

Run the fight

Round
1
3–5 rounds
Creatures
5
High

This round

Each sealed cabinet vents. Creatures within 20 feet of a vent make a Constitution save, taking thunder damage and becoming deafened on a failure. A creature can silence a cabinet by reducing it to 0 hit points or succeeding on a Arcana or Smith’s Tools check.

Win The party retrieves the oath before the end of round 3 and survives or drives off the raiders

Lose The oath is destroyed by area damage or a pressure surge

Party 6 players, level 17

System D&D 2024

Cheat sheet

Retrieve

Retrieve the ancient oath from the lectern before the end of round 3. A creature adjacent to it must use an action and succeed on a DC 20 Sleight of Hand check.

Win

The party retrieves the oath before the end of round 3 and survives or drives off the raiders.

Lose

The oath is destroyed by area damage or a pressure surge, or the party is forced to abandon the vault.

If it goes badly: A narrow service trench leads away from the entrance; creatures can flee through it, but the lectern cannot be recovered from there.

Forces

  • 1 × Bell-RaiserAC 19 · HP 332 · CR 18
  • 3 × Hearth-QuencherAC 17 · HP 230 · CR 12
  • 1 × Vent-Glass ColossusAC 18 · HP 207 · CR 12

Rounds

  • 1Each sealed cabinet vents.
  • 3The oath’s edges char and the lectern cracks.

Read aloud

Say this

The vault doors grind apart, and a plume drake surges through the gap, its bronze-lit jaws turning the air hot and metallic. Three salamanders spill toward the sealed cabinets while a giant of black glass tears free from the wall. The oath waits on the lectern as pressure ticks through the brass seams.

Forces

3

  • Bell-Raiser

    Bruiser

    1 of them
    AC
    19
    HP each
    332
    CR
    18

    Legendary Resistance (3/Day) · Phase-Shift Swimming

    Opens
    Glide through the vault entrance and use its strongest thunder attack against clustered intruders.
    Targets
    The creature concentrating on retrieving the oath, then anyone who silences a cabinet.
    Flees
    Fights until reduced to 0 hit points; it has no retreat plan.
    Open the monster

  • Hearth-Quencher

    Skirmisher

    3 of them
    AC
    17
    HP each
    230
    CR
    12

    Heat Drain Aura · Cryo-Explosion

    Opens
    Rush to the nearest sealed cabinet and feed on its heat; attack anyone trying to silence it.
    Targets
    Creatures beside the cabinets, especially those using tools or magic to stop the vents.
    Flees
    All flee when the Bell-Raiser falls.
    Open the monster

  • Vent-Glass Colossus

    Bruiser

    1 of them
    AC
    18
    HP each
    207
    CR
    12

    Pressure-Adapted · Refracting Facets · Shatter on Death

    Open the monster

More tactics

Vault Sentinel (Vent-Glass Colossus)

Opens
Block the route to the lectern and strike the nearest creature threatening the oath.
Targets
The creature approaching the lectern.
Flees
Fights until destroyed; it is bound to defend the vault.

What happens

3–5 rounds
  1. 1

    Initiative count 20, starting in round 1.This round

    Each sealed cabinet vents. Creatures within 20 feet of a vent make a Constitution save, taking thunder damage and becoming deafened on a failure. A creature can silence a cabinet by reducing it to 0 hit points or succeeding on a Arcana or Smith’s Tools check.

  2. 3

    End of round 3, if the oath has not been retrieved.

    The oath’s edges char and the lectern cracks. The oath is destroyed if it takes damage from an area effect or if a pressure surge hits the lectern.

The battlefield

Zones

  1. 1

    Cabinet Row25 ft

    Sealed cabinets line the walls, their brass seams ticking as pressure builds.

  2. 2

    Oath Lectern25 ft

    The ancient oath lies open on a stone lectern beneath a narrow shaft of blue light.

  3. 3

    Vent Trench25 ft

    A grated service trench runs behind the lectern, hot air trembling above its iron floor.

What the party can use

Sealed cabinets (c): each can be silenced at 0 hp or with an action and a DC 20 Arcana or Smith’s Tools check.
The lectern (L) stands in the open center of the vault; destroying it before the oath is taken ruins the document.
The cabinet vents fill the lower vault with ringing pressure; stone ribs provide half cover from creatures on the far side.

Scaling

XP budget53,600 of 70,200 XP
Weaker

High

One fewer Hearth-Quencher

The Vault Sentinel begins inert and activates only when a creature damages a cabinet or approaches the lectern.
As written

High

Stronger

High

One more Bell-Raiser

Add one salamander, entering from the service trench at the start of round 2.

Treasure

The rescued oath bears a heat-darkened seal and a final sentence that stops unfinished.

Media

0 images

No images yet.

Visual sheet

Turn Take the Oath Before the Vault Breaks into a sheet

A high-res, share-ready sheet you can post or print.