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Under the Dome: Eye of the Chaos Storm — A 5E Survival Encounter Beyond the Dome

The Domes of the world of Under the Dome offer shelter from the horrors of the Chaos Storms, but that protection only matters when you are safely inside. Outside the walls, the world belongs to the storm. The wind tears across the wasteland, the ground shifts beneath travelers’ feet, and reality itself seems to lose its grip on what is possible. Most people who venture beyond the Domes do so because they have no other choice. The desperate seek salvage, mercenaries hunt dangerous creatures, and explorers chase rumors of lost settlements swallowed by the storms. Every one of them knows the same truth: when the sky changes color, you run for shelter. Last Week we delved into Psionic Academies in Under the Dome, but today I decided to mix things up with a little adventure. Use this for Under the Dome or add Chaos storms into your world as you see fit.

This adventure brings the danger of the Chaos Storms directly to the table, using familiar Dungeons & Dragons 5th Edition mechanics to create a tense survival encounter. Rather than simply throwing monsters at the party, the storm becomes the enemy. Characters must work together, make difficult decisions, manage dwindling resources, and decide what they are willing to sacrifice to make it home alive.

The encounter is designed for a party of four characters around 5th level, but the difficulty can be adjusted for lower- or higher-level groups. It works as a standalone excursion, a complication during a salvage mission, or the beginning of a much larger adventure beyond the Domes.

Adventure Background: The Sky Turns Wrong

The characters are traveling through the wasteland between settlements when the warning signs begin. The wind dies. The distant horizon takes on a bruised violet hue. Fine black dust rises from the ground and hangs in the air, moving against the breeze. Then the characters notice the shadows: every shadow points toward the same distant point, regardless of where the light comes from.

A Chaos Storm is forming.

The party is several hours from the nearest Dome, too far to reach its gates before the storm arrives. Their only hope is to find shelter in the surrounding ruins, reach a nearby emergency refuge, or construct a temporary barrier strong enough to endure the worst of the storm.

There is one complication. The closest shelter is an old survey station, half-buried in the wasteland and marked on only the oldest maps. Its emergency beacon is still transmitting, but something inside has been transmitting a second signal—one that does not appear on any known frequency.

The characters have limited time to find the station, secure it, and survive the storm. And once the storm begins, they may discover that the danger outside is not the only thing trying to get in.

Starting the Encounter: The First Warning

Read or paraphrase the following when the party first notices the approaching storm.

The wind stops.

Not gradually. Not with the gentle fading of a breeze. One moment the wasteland is whispering around you, and the next there is absolute silence. Dust hangs motionless in the air. The distant ruins seem to lean toward the horizon, their jagged silhouettes outlined by a sky that has turned the color of an infected bruise.

Then the ground trembles.

Far beyond the black ridges, a wall of twisting light rises into the heavens. Lightning crawls sideways through clouds that spiral around an invisible center. Something enormous moves inside the storm, its outline visible for a heartbeat before the clouds swallow it.

A small device on your equipment begins to shriek. Its cracked display flashes a single warning: CHAOS EVENT — IMMINENT.

You have minutes to find shelter.

The characters have approximately 10 minutes of in-world time before the storm reaches them. Ask the players what they do. Characters who have traveled beyond the Domes may recognize the signs immediately, while inexperienced travelers may waste precious time trying to understand what they are seeing.

A character who succeeds on a DC 13 Intelligence (Nature or Arcana) check recognizes that this is a rapidly intensifying Chaos Storm. A character proficient with Survival can instead make a DC 13 Wisdom (Survival) check to identify the safest route toward the nearest shelter. On a success, the party locates the survey station without delay. On a failure, they still find it, but the detour costs them precious time: the storm reaches them as they arrive, leaving the station’s outer access partially buried in debris.

Scene One: The Race for Shelter

The survey station lies about half a mile away, tucked beneath the broken remains of an old transit overpass. Its outer shell is made from layered metal and ceramic plates, much of it scarred by decades of exposure. A faded symbol above the entrance identifies it as a pre-collapse weather monitoring facility.

The main entrance is jammed shut. A secondary maintenance hatch is visible on the station’s western side, but it is partially covered by rubble. The characters have only a few minutes before the storm hits in full.

This scene is a short skill challenge. The party needs three successes before two failures to enter the station before the storm’s worst effects begin. Each character should describe a meaningful action and make an appropriate ability check. The same character can contribute more than once, but encourage the players to vary their approaches.

These are suggested approaches, not a closed list. Reward creative ideas with an appropriate check, advantage, or an automatic success if the solution genuinely solves the problem. Spells that would reasonably bypass a task should work; the storm is dangerous, but it should not arbitrarily invalidate player abilities.

On a success: The party makes progress toward opening the station and getting everyone inside.

On a failure: The storm’s leading edge lashes the area with a surge of chaotic energy. The character making the check must succeed on a DC 13 Dexterity saving throw or take 1d6 force damage as a shard of airborne debris or a burst of unstable energy strikes them.

If the party earns three successes before two failures, they reach the station’s interior before the worst of the storm arrives. If they accumulate two failures first, they still get inside, but the storm catches them in the entrance. Each character must make a DC 14 Constitution saving throw, taking 2d6 force damage on a failure or half as much damage on a success. The station’s outer hatch also buckles, making the exit unusable until it can be repaired or cleared.

Either way, the characters get inside. The difference is how much strength, time, and equipment they have left to face what comes next.

Scene Two: Inside the Survey Station

The station’s interior smells of old dust, hot wiring, and something faintly metallic. Emergency lights flicker overhead. A narrow corridor leads to a central operations room, where battered consoles sit beneath a cracked observation window. Beyond the glass, the first waves of the Chaos Storm are already rolling across the wasteland.

Read or paraphrase the following:

The hatch slams behind you with a sound like a coffin lid. For one blessed second, there is only darkness and the sound of your own breathing.

Then the emergency lights stutter to life.

The station is a ruin. Cables hang from the ceiling, a collapsed storage rack blocks part of the corridor, and the observation window is webbed with cracks. A skeletal figure in a weather-stained uniform lies slumped over a console. Its fingers are still wrapped around a metal lever.

Outside, the sky splits open with violet lightning.

Every console in the room flickers awake.

One screen displays the station’s emergency seal. Another shows a live map of the surrounding wasteland. The third displays a message in blocky, repeating text:

DO NOT OPEN THE LOWER DOOR.

The survey station is not immediately safe. Its emergency systems are failing, and the characters need to stabilize the structure before the storm reaches full intensity. Three problems threaten their shelter: a damaged power regulator, a failing pressure seal, and an unstable support column beneath the observation room.

The characters can investigate and address these problems in any order. Each requires an action that takes approximately 10 minutes of in-world time, although characters may split up to work on different tasks simultaneously. This gives the party meaningful choices about whether to move quickly or work methodically.

The Power Regulator

The station’s power regulator is located in a small equipment alcove. Its casing has split open, exposing a cluster of crystal-like components that pulse with unnatural light. The regulator powers the emergency seal, lights, and internal sensors. If it fails, the station will be far more vulnerable to the storm.

A character can stabilize the regulator with a successful DC 14 Intelligence (Arcana) or Intelligence (Investigation) check. A character proficient with tinker’s tools or another appropriate tool set can use that proficiency instead, with the DM deciding the relevant ability based on the approach.

A character who succeeds restores the station’s emergency power. The room lights stabilize, the seal begins to hum, and the party gains advantage on its first check to reinforce the station later in the encounter.

On a failure, the regulator discharges a pulse of unstable energy. The character takes 2d6 lightning damage, or half as much on a successful DC 13 Dexterity saving throw. The regulator remains damaged, but another attempt is possible.

The Pressure Seal

The station’s main emergency seal is a thick mechanical barrier designed to protect the interior from toxic dust and extreme atmospheric conditions. The outer hatch has warped, and the seal is no longer engaging properly.

A character can repair it with a successful DC 14 Strength (Athletics) check to force the mechanism into alignment, a DC 14 Dexterity check using thieves’ tools, or a DC 14 Intelligence (Investigation) check to identify and correct the fault. A character who uses appropriate tools and has proficiency can add their proficiency bonus as normal.

If the seal is repaired, the station resists the storm’s worst wind pressure. During the final scene, the party will not need to make the additional group saving throw caused by a failing seal.

If the check fails, the character hears metal groan and snap. The seal remains partly open, allowing chaotic dust to creep into the station. A second attempt is possible, but the character making it must first succeed on a DC 13 Constitution saving throw or gain one level of exhaustion from the dust and strain. Use the exhaustion rules from the version of 5E your table plays.

The Support Column

A heavy support column beneath the observation room has fractured near its base. If it gives way, the room’s ceiling could collapse, cutting off access to the main corridor and exposing everyone inside to the storm.

The characters can shore up the column with salvage, rope, metal braces, or magic. A successful DC 14 Strength (Athletics) check, Intelligence (Investigation) check, or an appropriate tool check stabilizes the support.

On a success, the column holds through the storm. On a failure, the character hears a deep crack as the column shifts. The station shudders, and each character in the operations room must succeed on a DC 13 Dexterity saving throw or take 1d6 bludgeoning damage from falling debris.

The column can be attempted again, but the characters need to find more material to brace it. If they have already searched the station, the DM can require them to spend another 10 minutes salvaging parts from a storage room.

Scene Three: The Storm Arrives

Once the characters have had an opportunity to address the station’s problems—or after about 30 minutes of in-world time—the Chaos Storm reaches its full fury.

Read or paraphrase the following:

The first impact sounds like a mountain falling.

The station lurches. Every light goes dark, then returns in a violent flicker. Something scrapes across the outside walls, moving from one end of the building to the other. The observation window flashes white as lightning crawls across its surface, leaving glowing veins in the glass.

The air fills with a low, rhythmic pulse. It is almost like a heartbeat, except the sound seems to come from inside your bones.

Then the station’s lower door opens by itself.

Beyond it, a staircase descends into darkness. At the bottom, something begins to knock.

The storm has reached the station, and the characters must now endure its effects. Run this as a three-round survival sequence. Each round represents a brief but dangerous period in which the characters must protect themselves, reinforce the station, or investigate the strange activity below.

At the start of each round, every character must make a DC 13 Constitution saving throw. On a failure, the character takes 1d6 force damage as the storm’s chaotic energies penetrate the station. A character who has a level of exhaustion, is already injured, or has been exposed to the storm earlier should still make the normal save; avoid piling on arbitrary penalties simply because the scene is dangerous.

If the pressure seal was not repaired, each character must also succeed on a DC 13 Dexterity saving throw at the start of the first round or take 1d6 slashing damage from debris and metal fragments driven through the opening. This additional hazard occurs only once, rather than every round.

During each round, a character can use their action to perform one of the following tasks: reinforce the station’s structure with a DC 13 Strength (Athletics) check; stabilize the regulator with a DC 13 Intelligence (Arcana) or tool check; monitor the storm’s progression with a DC 13 Wisdom (Perception) or Intelligence (Investigation) check; or help another character, granting that character advantage on their next ability check or saving throw against the storm. Other creative actions should be encouraged if they fit the situation.

The first successful reinforcement check prevents a structural failure. The first successful regulator check prevents an additional power surge. A successful monitoring check reveals that the storm is behaving unnaturally: its energy is concentrating around the station’s lower level, not the exposed observation room.

The party can survive the storm by weathering all three rounds. But the strange knocking from below raises a question: why is the storm gathering around the lower door?

Scene Four: Something Beneath the Station

The characters have survived the first wave of the storm, but the station’s sensors begin to report impossible readings. The lower level is registering as both empty and occupied. Its temperature is dropping, although the equipment says the room is burning hot. The knocking continues, always three slow taps followed by a pause.

If the characters investigate, they discover that the lower door leads to an old containment chamber. The chamber was built to hold a device called a Chaos Anchor, an experimental machine intended to measure and redirect storm energies. Its operators apparently discovered something they could not control. The skeletal figure at the console was not trying to keep the storm out. It was trying to keep something inside.

The door has opened because the storm has disrupted the containment field.

A character who examines the console and succeeds on a DC 14 Intelligence (Arcana) or Intelligence (Investigation) check discovers a final log entry:

Containment failure imminent. The entity is responding to the storm. It is not a creature in the conventional sense. It is a wound in the world that has learned to move.

If the Anchor loses power, do not attempt retrieval.

Do not open the lower door.

The characters now face a choice. They can remain in the operations room and let the storm pass, attempt to restore the containment field, or descend into the chamber to investigate the source of the disturbance. There is no single correct decision. Each option carries a different risk and a different possible reward.

Option One: Seal the Lower Door

The safest option is to close the lower door and reinforce its locking mechanism. A character can make a DC 14 Strength (Athletics) check to force the door shut, followed by a DC 14 Intelligence (Arcana) or tool check to reengage its locking system.

Both checks are needed. Other characters can assist by bracing the door, securing cables, or stabilizing the power supply. If the party succeeds, the knocking stops. The station’s systems stabilize, and the entity remains contained until the storm passes.

If either check fails, the door slams open again, and a pulse of chaotic energy sweeps through the chamber. Each character within 10 feet of the door must make a DC 13 Dexterity saving throw, taking 2d6 force damage on a failure or half as much on a success. The party can try again, but the entity grows more active with each attempt.

Option Two: Restore the Chaos Anchor

The party can attempt to restore the device’s containment field. This requires descending into the lower chamber, where the walls are covered in strange markings that seem to move when nobody looks directly at them.

The Chaos Anchor is a metal framework surrounding a floating crystal, its surface fractured by thin lines of violet light. Three power conduits feed into the frame, but only one remains functional. The others must be repaired or rerouted.

To restore the Anchor, the party must achieve three successes before two failures. Suitable checks include DC 14 Intelligence (Arcana) to understand the device, DC 14 Dexterity checks using tinker’s tools to repair the conduits, or DC 14 Strength (Athletics) checks to reposition damaged components. Creative magical solutions can also contribute.

On each failed check, the character making it must succeed on a DC 13 Constitution saving throw or take 2d6 force damage as the chamber briefly shifts out of alignment with reality.

If the party succeeds, the containment field reactivates. The knocking stops, the violet light fades, and the storm’s energy begins to disperse around the station. The characters have not destroyed the anomaly, but they have restored the mechanism that keeps it contained.

If the party fails, the Anchor overloads. The chamber erupts with chaotic energy, and the characters must retreat immediately. Each character must make a DC 14 Dexterity saving throw, taking 3d6 force damage on a failure or half as much on a success. The storm still eventually passes, but the containment chamber is ruined, and whatever was inside may no longer be confined.

Option Three: Open the Chamber

Some adventurers cannot resist the promise of a secret hidden beneath a forgotten research station. If the characters deliberately open the containment chamber, the entity emerges.

Use the following creature as a short, dangerous encounter for a party of four characters around 5th level.

The Chaos Wraith does not fight like a normal creature. It drifts through walls, lashes out at the nearest living target, and retreats through the floor when wounded. It is drawn to the energy of the Chaos Storm, and its presence makes the containment chamber flicker between several possible versions of itself.

The party’s goal does not need to be killing the wraith. They can escape to the operations room, restore the Anchor while avoiding the creature, or lure it into a damaged section of the station and seal it behind them. If they reduce it to 0 hit points, the wraith collapses into a cloud of violet sparks. Its destruction causes the storm to surge briefly, but the party can survive by returning to the operations room and enduring the remaining storm rounds.

If the party restores the Anchor while the wraith is still active, the containment field pulls it back into the crystal, ending the encounter without requiring the characters to defeat it in combat.

The Final Test: The Storm Breaks

When the party has completed its chosen course of action and survived the three-round storm sequence, read or paraphrase the following:

The sound outside slowly changes. The thunder becomes distant, the lightning fades from the walls, and the terrible pressure in the air begins to lift.

For the first time in what feels like hours, the station stops shaking.

Beyond the cracked observation window, the storm is retreating across the wasteland. Its violet clouds unwind into the distance, leaving behind a sky streaked with unnatural colors. The ground has changed. New ridges rise where none existed before, and a line of black glass stretches toward the horizon.

Your equipment begins to work again. The station’s emergency beacon flickers to life.

Then, from somewhere deep beneath the floor, you hear three slow knocks.

Pause.

Three more.

Whatever happened here, it may not be over.

If the characters successfully restored the Chaos Anchor, the knocks are faint and distant. If they sealed the lower door, they hear nothing further from the chamber. If they opened the chamber and allowed the wraith to escape, the final knocks may come from somewhere outside the station.

The party has survived the Chaos Storm, but the adventure has left them with new questions. What was the survey station truly studying? Why did the storm gather around the lower level? And how many other abandoned research facilities are scattered across the wasteland, each hiding something that should never have been discovered?

Rewards and Consequences

Surviving a Chaos Storm is an accomplishment in itself, especially for travelers who have spent most of their lives sheltered beneath a Dome. The party should receive the usual experience points for overcoming the encounter, including any combat, exploration, and problem-solving rewards appropriate to your table.

If the characters restore the Chaos Anchor, they may recover a stormglass core, a fist-sized crystal that remains faintly warm even after the storm passes. It can be sold to an Arcane College, a Grind Syndicate, or a faction interested in studying Chaos Storms. Its value depends on the campaign, but it should be valuable enough to make the party consider returning to the station.

If the characters recover the station’s research logs, they discover references to other survey stations and an unidentified location called the Ninth Meridian. The logs suggest that the storms do not form randomly. Someone—or something—may be influencing their paths.

If the party survives but leaves the Chaos Anchor damaged, the station could become a future adventure site. A faction may send the characters back to retrieve the remaining research, or a storm could expose the facility to a new threat.

Most importantly, the characters should return to the Dome with a story. Survivors of the wasteland are rare, and people inside the Dome may regard the party with admiration, suspicion, or outright disbelief. Their experience could earn them a reputation among mercenaries and explorers—or attract the attention of people who would prefer that the truth about the survey station remain buried.

Scaling the Encounter for Your Campaign

For a lower-level party, reduce the storm’s damage to 1d4 force damage per failed saving throw, lower the skill challenge DCs to 11–12, and remove the Chaos Wraith’s Multiattack. For a stronger party, increase the storm’s saving throw DCs to 15, raise the wraith’s hit points to 65, or add another environmental complication during the final sequence.

For a campaign focused on horror, emphasize the station’s impossible readings, the moving markings, and the feeling that the storm is responding to the characters’ actions. For a more action-oriented game, make the race to the station more dangerous, add collapsing terrain, and have the party make hard choices about what equipment they can carry to safety.

The most important rule is to make the storm feel like a force of nature that cannot be defeated by simply dealing enough damage. The characters can outthink it, prepare for it, endure it, or find shelter from it. They cannot punch the sky until it stops.

Bringing Chaos to Under the Dome

The Chaos Storms are more than a reason for the people of this setting to live beneath massive protective structures. They are a constant reminder that civilization exists on borrowed time. Beyond the Domes lie lost technologies, strange creatures, abandoned settlements, and mysteries that might reshape the world—or destroy what remains of it.

This encounter gives the party a chance to experience that danger firsthand. It puts familiar 5E abilities and mechanics to work in a different way, asking players to think beyond combat and cooperate under pressure. The storm becomes a living obstacle, the station becomes a puzzle, and the mystery beneath the floor becomes a choice with consequences.

And when the characters finally return to the safety of the Dome, they may find that the most frightening part of the journey is not what they encountered outside.

It is what followed them home.

Thanks for reading. Until Next Time, Stay Nerdy!!