Mars Under Glass
Two Plans for One Planet
Two rival terraforming corporations operate on Mars, each running a different environmental system inside separate dome networks. TerraWest is converting the western hemisphere through slow biological processes: engineered mosses, soil bacteria, and atmospheric seeding. AstraNova controls the eastern domes with mechanical climate regulation: thermal processors, manufactured atmosphere, and synthetic water cycling. Both systems work. They are also chemically incompatible. If the dome seals fail, the two atmospheres will mix and produce conditions that support neither approach. The settlers who live between the dome networks are caught in a corporate cold war where the planet itself is the weapon.
“TerraWest says their moss will make this planet breathable in 200 years. AstraNova says their machines will do it in 50. Neither of them mentions what happens to my family if both of them try at the same time.”
- Sula Hargreaves, Dome 7 resident
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1. Setting Overview & Tone
High-Concept Pitch: Mars Under Glass is a colony story where the threat is not the hostile planet but the two organizations trying to fix it. Both terraforming approaches are scientifically valid. Both would work if the other did not exist. The settlers did not choose a side. They chose a planet, and the planet came with a corporate conflict built into the air they breathe.
Tone: Domestic, political, and claustrophobic. Life inside the domes is ordinary in most respects: people work, raise children, argue about neighborhood issues, and complain about the food. The extraordinary part is that the walls are the only thing keeping the atmosphere compatible with human lungs, and two corporations are fighting over who controls the walls.
Sensory Pillars:
- Sight: The red Martian landscape visible through dome glass, beautiful and lethal. The visual difference between a TerraWest dome (green-tinged air, living moss on interior walls, warm and humid) and an AstraNova dome (clear air, metallic surfaces, climate-controlled to a precise 21 degrees). The neutral zone between domes where the ground is raw regolith and the sky is unfiltered.
- Sound: The low whistle of dome pressure equalization. The hum of AstraNova’s climate processors, constant and mechanical. The drip of condensation in a TerraWest dome where the humidity is deliberately kept high. The alarm that means a seal is degrading, which everyone recognizes and nobody discusses casually.
- Touch & Smell: TerraWest domes smell like wet earth and growing things. AstraNova domes smell like nothing, which is engineered and slightly unsettling. The neutral zone smells like dust and cold metal. The texture of dome glass under a hand: warm inside, cold outside, vibrating faintly with wind pressure.
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2. The Dome Networks
TerraWest Domes (Western Hemisphere) are organic environments: engineered plants grow on the walls, biological filters clean the air, and the temperature fluctuates with the day cycle to support living systems. The domes feel alive. They are also slower to repair when damaged and dependent on biological processes that cannot be rushed.
AstraNova Domes (Eastern Hemisphere) are mechanical environments: air composition, temperature, humidity, and light are all machine-controlled. The domes are efficient, predictable, and sterile. Repairs are fast because every component is standardized. The atmosphere tastes faintly of ozone near the processors.
The Neutral Zone is the unpressurized surface between dome networks. Travel across it requires EVA suits and takes 2-6 hours depending on distance. The Neutral Zone is technically ungoverned territory. In practice, both corporations monitor it for unauthorized crossings, equipment dumps, and sabotage staging.
Dome 7 is a hybrid settlement that sits on the boundary between the two networks. It was originally a TerraWest installation that AstraNova partially retrofitted during a territorial dispute. It now runs both systems simultaneously, which works most of the time and produces unpredictable atmospheric events when the biological and mechanical systems interact. The residents of Dome 7 are the most experienced people on Mars at handling environmental emergencies. They are also the most tired.
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3. Factions
TerraWest believes biological terraforming is the only approach that produces a self-sustaining planet. Their project director, Dr. Kenji Saito, is a patient man who thinks in centuries and cannot understand why settlers want results in their lifetime. TerraWest’s internal problem is funding: biological terraforming is slow, investors want returns, and the pressure to accelerate the timeline leads to untested biological agents being deployed in occupied domes.
AstraNova believes mechanical control is the only approach that keeps settlers safe during the transition. Their operations chief, Director Lena Cyr, is efficient, data-driven, and genuinely believes that biological terraforming is an uncontrolled variable that will get people killed. AstraNova’s internal problem is dependency: their domes require constant power and maintenance. A prolonged equipment failure would make an AstraNova dome uninhabitable faster than a TerraWest dome, and Cyr knows it.
The Dome Council is an informal governing body made up of elected residents from both dome networks. It has no legal authority over either corporation but significant social authority over the settlers. The Council has been demanding environmental safety disclosures from both corporations. Neither has complied fully. Council Chair Sula Hargreaves suspects both corporations are conducting experiments that could affect neighboring domes.
The Boundary Runners are independent settlers who live in the Neutral Zone, moving between dome networks in EVA suits. They smuggle goods, carry messages, and maintain an underground network of emergency shelters. They know the Martian surface better than anyone and serve as the informal early-warning system when dome conditions change. Their leader, Tomás Ochoa, has been documenting atmospheric readings in the Neutral Zone that suggest both terraforming systems are already leaking.
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4. Unique Mechanic: Dome Pressure
At the start of each session, the Storyteller rolls a hidden d6 for each dome the characters occupy or visit.
| Roll | Event |
|---|---|
| 1 | Stress Event: Seal degradation, atmospheric imbalance, or equipment malfunction. Characters must respond within the scene or the dome advances toward breach. |
| 2-3 | Minor fluctuation: Temperature shift, humidity spike, or brief alarm. Noticeable but not dangerous. Provides narrative texture. |
| 4-6 | Stable. Normal operations. |
Breach progression: A dome experiencing its second unresolved stress event in a session enters Pre-Breach. At Pre-Breach, non-essential corridors are sealed automatically, residents are directed to shelter zones, and the characters have two scenes to stabilize the system. If they fail, the dome reaches Breach: atmospheric mixing with the exterior. Everyone inside has 10 minutes to reach a sealed section or an EVA suit.
Cross-contamination: If a TerraWest dome and an AstraNova dome both experience stress events in the same session, their atmospheres may interact in the Neutral Zone or through shared infrastructure. The Storyteller describes the specific chemical reaction (corrosive fog, oxygen depletion, toxic precipitation) based on which systems are involved.
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5. Character Archetypes
The Dome 7 Technician
You maintain both biological and mechanical systems in the most unpredictable dome on Mars. You are not formally trained in either corporation’s technology. You learned by fixing things that broke in ways neither corporation anticipated.
- Drive: “Keep Dome 7 standing until someone with actual authority makes the corporations stop using my home as a test case.”
- Approach Distribution: Force 2 | Finesse 3 | Mind 2 | Presence 1
The Dome Council Representative
You were elected because you yell at corporate representatives and people find that satisfying. You are beginning to realize that yelling accomplishes less than you promised and that the environmental data you have been requesting, if it says what you suspect, will require action that nobody in the Council is prepared for.
- Drive: “Get the data. Read the data. Make the data public before either corporation can reclassify it.”
- Approach Distribution: Force 1 | Finesse 1 | Mind 3 | Presence 3
The Boundary Runner
You live in the Neutral Zone. You own an EVA suit, a cargo sled, and a network of contacts in both dome networks. You have been measuring atmospheric readings in the Zone for two years. The numbers are changing in ways that neither corporation’s public models predict.
- Drive: “Map what is actually happening to this planet, not what either corporation says is happening.”
- Approach Distribution: Force 2 | Finesse 3 | Mind 2 | Presence 1
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6. Starter Scenario & Why It Matters
The Fog Event: A dense, corrosive fog has formed in the Neutral Zone between Dome 7 and AstraNova Dome 12. The fog is a chemical reaction between TerraWest’s biological off-gassing and AstraNova’s atmospheric venting. It is dissolving EVA suit seals. Three Boundary Runners are trapped between domes. TerraWest denies responsibility, citing natural atmospheric variation. AstraNova denies responsibility, citing TerraWest’s uncontrolled biological agents. The Dome Council demands an emergency meeting. Director Cyr offers to rescue the Runners using AstraNova equipment if the Council endorses AstraNova’s expansion proposal. Dr. Saito offers to neutralize the fog using a TerraWest biological agent that has not been tested in the Neutral Zone. The characters must rescue the Runners, determine the actual cause of the fog, and prevent the crisis from being used as leverage by either corporation. The fog is getting thicker.
Why It Matters: Mars Under Glass asks what happens when two valid approaches to the same problem are forced to coexist in a space that only has room for one. The corporations are not villains. Both genuinely believe their method will make Mars habitable. The settlers are not victims. They are participants in a colonial project that was oversold and underprepared. The planet does not care about any of them. The question is whether the people on Mars can cooperate before the chemistry makes the choice for them.