ELEMENT × EXTREMOPHILE

The Biogeochemistry Card Game — Complete Rulebook v1.0
"Every combo is real. Every failure teaches. Every victory is a biosphere."

Contents

1. Overview & Game Identity 2. Components 3. Setup 4. Turn Structure 5. Resource System 6. Organism Card Anatomy 7. Syntrophy Rules 8. Competitive Exclusion 9. Environmental Event Cards 10. Scoring 11. Suit-Specific Mechanics 12. Project AXIS Cooperative Mode 13. Tournament Format 14. Manufacturing & Kickstarter 15. Edge Case FAQ 16. Scientific Glossary

1. Overview & Game Identity

Element × Extremophile is a resource-engine card game with area control and tableau-building. It is explicitly not a combat game. There are no hit points. Organisms do not fight — they outcompete, poison, or starve each other through thermodynamic reality.

The Core Innovation: In Magic: The Gathering, card combos are designed by game designers. In Element × Extremophile, combos are constrained by actual biogeochemistry. You cannot pair a strict anaerobe with an oxygenic phototroph in the same zone without a spatial separation card. A methanogen MUST have an H₂ source — if its syntrophic partner dies, it starves. You cannot make up combos. You discover real ones.
42
BIOENERGY POINTS TO WIN

~42 kJ/mol = thermodynamic minimum for ATP synthesis.
Also: the answer to everything.

Four Tension Axes

AxisTrade-off
Energy vs. FragilityHigh-energy organisms (phototrophs, iron oxidizers) score fast but need narrow conditions. Low-energy organisms (fermenters) score slowly but survive everything.
Independence vs. SyntrophySolo organisms function alone but generate modest BP. Syntrophic consortia generate bonus BP but collapse if one member is removed.
Colonization Speed vs. DepthRushing to claim zones gives flexibility; deep metabolic networks give exponential scoring.
Specialization vs. VersatilitySpecialists score higher per turn in their niche; generalists survive disruption.

2. Components

ComponentQtyNotes
Organism Cards (Tarot 70×120mm)12030 per suit: Pyro / Litho / Photo / Halo
Event Cards40Red card back; 4 categories
Equipment Cards20Silver card back; tools, CRISPR mods
Central Board (4-fold)1~500×500mm; shared zones + Electron Tower reference
Planet Board (3-fold)1~400×600mm; Project AXIS mode only
Player Mats4~200×300mm each
Zone Cards16Define habitat conditions
Quick Reference Cards4One per player
Energy Tokens (yellow)60Denominations: 40×1, 15×3, 5×5
Carbon Tokens (black cubes)30
Electron Tokens (blue crystals)30Translucent acrylic — the best component
Nitrogen / Sulfur / Iron tokens6020 each; Iron = heavy metal cubes (thematic)
pH / Temperature / Radiation tokens35
Stress Tokens (red cubes)20
Syntrophy Link tokens (wooden arrows)15Double-headed
Score Trackers (meeples)4Colors: Red, Gray, Gold, Purple
Redox Cascade Marker1Electron-shaped wood piece
Custom dice (d6, element faces)2

3. Setup

  1. Shuffle Organism, Event, and Equipment decks separately.
  2. Place Central Board in center. Set Redox Cascade Marker to "Oxic".
  3. Each player takes: 1 Player Mat, 1 Score Tracker (place at 0), 1 Quick Reference Card.
  4. Deal each player 5 Organism Cards face-down. Players look privately.
  5. Reveal 4 Organism Cards face-up as the central Gene Pool.
  6. Place Habitat Zone Cards based on player count:
PlayersPersonal ZonesShared ZonesTotal
24 each08
33 each312
42 each412
  1. Give each player starting resources: 5 Energy, 3 Carbon, 2 Electrons, 1 Nitrogen.
  2. First player: most recently near a body of water. Clockwise play.

4. Turn Structure

1
Draw
Take 2 cards from any source
2
Play
Up to 2 actions
3
Metabolize
All organisms produce & score
4
Event
Last player only: flip event card

Phase 1: Draw

Draw 2 cards from any combination of:

Hand limit: 7 cards. Discard down immediately if exceeded. Discarded organisms → Extinction Pile. Organisms in the Extinction Pile add 2 Carbon to their last zone (real lysis chemistry).

Phase 2: Play (up to 2 actions)

ActionCostNotes
A. Deploy OrganismPrinted deploy costMust pass Viability Check (see below)
B. Play EquipmentPrinted costAttach to organism or zone
C. Move Organism1 EnergyTo adjacent zone; must pass Viability Check in new zone
D. Activate Special AbilityVariesTap organism (turn sideways); untaps at start of your next turn
E. Initiate Syntrophic Pair0Declare two organisms in same zone as partners; place Syntrophy Link token

Viability Check

When deploying or moving an organism, ALL of the following must match the zone:

Phase 3: Metabolize

For each of your organisms in a viable zone:

  1. Consume: remove required inputs from zone supply. If unavailable → organism is starving → gains 1 Stress Token. At 3 Stress Tokens, organism dies.
  2. Produce: add output resources to zone supply.
  3. Score: add the organism's Energy Yield to your BP total.
Stress Tokens: 1 Stress = no immediate effect. 2 Stress = half yield (round down). 3 Stress = organism DIES → Extinction Pile → releases 2 Carbon to zone.

Phase 4: Environment

Only triggered after the last player's turn in each round. Flip the top Event card and resolve immediately. When the Event deck empties, the game ends at the completion of that round.

5. Resource System

ResourceTokenFunction
Energy (ATP)Yellow discUniversal currency. Pay deploy costs, move organisms, buy equipment. Also the scoring unit.
CarbonBlack cubeRequired by heterotrophs. Produced by autotrophs and fermenters.
Electrons (e⁻/H₂)Blue crystalReducing equivalents. Flow from donors → acceptors through the electron tower.
NitrogenGreen discRequired for growth. Nitrogen fixers produce it; all organisms consume it slowly.
SulfurOrange discCycled between SO₄²⁻ (oxidized) and H₂S (reduced) forms.
IronRust metal cubeCycled between Fe²⁺ and Fe³⁺. Iron cubes are physically heavy — thematic.

Zone Resource Generation (start of each round)

Zone TypeResources Generated
Surface / Oxic+2 Energy, +1 Carbon, +1 Nitrogen
Subsurface+1 Energy, +1 Iron or Sulfur
Deep+1 Energy, +1 Sulfur
Core Interface+2 Iron, +1 Sulfur, 0 Carbon, 0 Nitrogen

6. Organism Card Anatomy

┌─────────────────────────────────┐ │ [SUIT ICON] [RARITY GEM] │ │ │ │ ╔═════════════════════════╗ │ │ ║ [ORGANISM ART] ║ │ │ ╚═════════════════════════╝ │ │ │ │ ORGANISM NAME │ │ Genus species (italicized) │ │ ───────────────────────────── │ │ TYPE: Archaea / Bacteria / │ │ Eukarya / Consortium │ │ METABOLISM: e.g., "Sulfate │ │ Reducer — H₂ + SO₄²⁻ → │ │ H₂S + H₂O" │ │ ───────────────────────────── │ │ DEPLOY COST: ⚡2 🟢1 │ │ INPUTS: 🔵1 (e⁻) + 🟠1 (SO₄) │ │ OUTPUTS: 🟠1 (H₂S) + 🟡1 (E) │ │ ENERGY YIELD: ⚡ 2 BP/turn │ │ ───────────────────────────── │ │ REQUIREMENTS: │ │ Temp: 20–80°C | pH: 5–9 │ │ O₂: Strict Anaerobe │ │ Pressure: Low–High │ │ ───────────────────────────── │ │ ABILITY: [Special text] │ │ SYNTROPHY: pairs with │ │ [H₂-producing fermenters] │ │ ───────────────────────────── │ │ FLAVOR: "Found in deep-sea │ │ hydrothermal sediments..." │ │ ───────────────────────────── │ │ [ELECTRON TOWER: E°' = -217mV]│ │ [ID: LI-U-014] │ └─────────────────────────────────┘

Card ID Format: [SUIT]-[RARITY]-[NUMBER]  |  Suits: PY / LI / PH / HA  |  Rarity: C / U / R / L

Rarity borders: Common = single line · Uncommon = double · Rare = triple · Legendary = thick + internal pattern

7. Syntrophy Rules

Syntrophy models real obligate metabolic partnerships. The output of organism A must include a resource that is the input of organism B (or vice versa).

Establishing Syntrophy (costs 1 action)

  1. Two organisms must be in the same habitat zone
  2. One's output must include the other's required input
  3. Declare the link; place a Syntrophy Link token between them

Benefits

Risks

Pre-Printed Syntrophic Pairs

Pair NameOrganismsMechanismBonus
The Methanogenic CoupleFatty acid oxidizer + Hydrogenotrophic methanogenFatty acid oxidation only favorable when methanogen removes H₂ (ΔG shifts +48 → -22 kJ/mol)+3 BP (obligate)
AOM ConsortiumANME archaea + Sulfate-reducing bacteriumReverse methanogenesis coupled to sulfate reduction+4 BP (highest in game)
Nitrification TeamAmmonia oxidizer (AOB) + Nitrite oxidizer (NOB)NH₃ → NO₂⁻ → NO₃⁻ (complete nitrification)+2 BP
Iron CycleIron oxidizer + Iron reducerFe²⁺ ↔ Fe³⁺ closed loop+5 BP (cycle bonus)
Cable BacteriaCable bacterium + Any sulfide producerLong-distance electron transport through filament — unique: links adjacent zones+3 BP + cross-zone link

8. Competitive Exclusion

When two players' organisms occupy the same shared zone and compete for the same electron acceptor:

  1. Compare E°' (Electron Tower Position): Higher = more favorable = wins. Loser gets 0 energy yield and gains 1 Stress Token.
  2. If tied (same acceptor, same E°'): Lower Km (Affinity Rating on card) wins.
  3. If still tied: Incumbent (deployed first) wins.

Losing organism gains 1 Stress per turn of exclusion. Players can retreat (Move action) before 3 Stress accumulate.

Competitive Exclusion does NOT apply to syntrophic partners using different resources, or organisms on different metabolic pathways.

The Electron Tower — Dominance Map

Energy flows from low potential (donors) to high potential (acceptors). Greater ΔE = more energy released. Higher-potential acceptors always outcompete lower-potential acceptors.

1
O₂ → H₂O (Aerobic respiration)
+820 mV
PHOTO
2
NO₃⁻ → N₂ (Denitrification)
+751 mV
LITHO
3
MnO₂ → Mn²⁺ (Manganese reduction)
+380 mV
LITHO
4
Fe³⁺ → Fe²⁺ (Iron reduction)
-77 to +200 mV*
LITHO
5
SO₄²⁻ → H₂S (Sulfate reduction)
-217 mV
LITHO
6
CO₂ → CH₄ (Methanogenesis)
-244 mV
PYRO
7
CO₂ → Acetate (Acetogenesis)
-290 mV
PYRO
8
Internal: Fermentation (no external acceptor)
N/A
PYRO

*Iron E°' is pH-dependent — the game models this with pH Modifier Tokens (game mechanic).

The Redox Cascade: as O₂ is consumed, the Redox Cascade Marker moves down, opening niches for anaerobes. Players experience the real stratification of a biofilm, sediment, or stratified lake in real time.

9. Environmental Event Cards (40 total)

Revealed at the end of each full round. Resolved immediately by all players.

🌋 Hydrothermal Vent Eruption
Random deep zone: all organisms gain +3 BP this turn. Zone temperature +50°C for 2 rounds. Organisms exceeding temp range take 2 Stress.
💥 Oxygen Catastrophe
All zones gain +3 O₂. Strict anaerobes take 2 Stress/turn until O₂ consumed. Aerobes score double.
⚡ Solar Flare
Surface zones gain +3 Radiation. Non-resistant organisms take 2 Stress. Melanin Radiotroph: triple energy yield.
🌑 Impact Winter
All surface zones lose Light for 3 rounds. Phototrophs produce nothing. Chemolithotrophs unaffected.
🧪 pH Crash
All surface zones drop to pH 2 for 2 rounds. Non-acidophiles take 1 Stress/turn.
🦠 Phage Attack
Choose one zone. Roll d6 per organism: 1–2 = organism dies. CRISPR-equipped organisms immune.
🔗 Horizontal Gene Transfer
Your organism gains one of an opponent's abilities for 3 rounds (same zone). Real biology!
☁️ Volcanic Degassing
All zones: +2 Sulfur, +1 Carbon. Surface zone pH drops by 2 (acid rain).
💎 Mineral Vein Exposed
One zone: +5 Iron, +3 Sulfur. Iron/sulfur metabolizers score double this round.
🌿 Nutrient Bloom
All surface zones: +3 Carbon, +2 Nitrogen. Heterotrophs score double this round.
🏔️ Tectonic Uplift
One deep zone becomes surface zone. High-pressure adapted organisms take 2 Stress.
📈 Bloom and Crash
Your highest-scoring organism triples output this turn, then dies next turn (population overshoot).

10. Scoring

+E
Organism metabolism per turn
+2
Syntrophic pair bonus per turn
+3
Per link in network of 3+
+5
Closed biogeochemical cycle per turn
+2
Zone control per zone
+1
Per distinct metabolic type (endgame)

Victory: First to 42 BP, or highest BP when Event deck empties.

Tiebreaker: Most organisms alive → Most syntrophic links → Most distinct metabolic types → Shared victory.

11. Suit-Specific Mechanics

🔴 PYRO — Thermophiles "The Forge"

Passive — Heat Shield: Pyro organisms ignore temperature increases from events. Never stressed by heat.

Suit Mechanic — Thermal Gradient Bonus: Pyro organisms in 3+ zones at different temperature ranges: +1 BP/turn per additional zone.

Legendary — Strain 121 (Geogemma barossii): Deploy in ANY zone regardless of temperature. Zone becomes inhospitable to non-Pyro organisms for 2 turns. Grows at autoclave temperature (121°C) — real organism.

⚙️ LITHO — Chemolithotrophs "The Foundation"

Passive — Rock Eaters: Litho organisms extract resources from zones with 0 organic carbon. They feed on rock.

Suit Mechanic — Electron Shuttle: Litho organisms can pass electron tokens to adjacent zones at no action cost.

Legendary — Desulforudis audaxviator: Completely self-sufficient — fixes N, fixes C, uses radiolytic H₂. 4 BP/turn with no partners. Cannot form syntrophic pairs (obligate loner). Real organism found 3.1 km underground, South Africa.

☀️ PHOTO — Phototrophs "The Engine"

Passive — Light Harvest: Photo organisms generate +1 Energy Token per turn for their zone.

Suit Mechanic — Oxygen Economy: Oxygenic phototrophs produce O₂ each turn. Too much O₂ poisons your own anaerobic partners. Manage the balance.

Legendary — Cyanobacterial Mat Formation: Requires 3 Photo organisms in one zone. Creates simultaneous oxic (surface) + anoxic (interior) microenvironment — both aerobic AND anaerobic organisms can coexist. +3 BP/turn for the formation.

🛡️ HALO — Polyextremophiles "The Shield"

Passive — Stress Resistance: Halo organisms have +2 to all Event resistance. Lose 1 Stress Token per turn naturally.

Suit Mechanic — Polyextremophile Bonus: +1 BP/turn for each additional stress type tolerated beyond primary.

Legendary — Melanin Radiotroph (Cladosporium sphaerospermum): Converts ionizing radiation directly into metabolic energy. Triple energy yield in irradiated zones. The real organism grows toward radiation sources at Chernobyl — mechanism still uncharacterized.

12. Project AXIS — Cooperative Bioforming Mode

2–4 players, cooperative. Collectively establish a self-sustaining biosphere on a hostile planet. Win together or die together.

The 6-Zone Planet Board

ZoneDepthTempConditions
1. Surface0-60 to 40°CLight: YES · O₂: Trace · Radiation: HIGH
2. Cryosphere0–100m-20 to 5°CLight: NO · O₂: None · Acceptors: SO₄²⁻, Fe³⁺
3. Silicate100m–1km5–60°CLight: NO · O₂: None · Donors: H₂(radiolysis), Fe²⁺
4. Upper Mantle1–10km60–200°CLight: NO · Acceptors: CO₂, S⁰, Fe³⁺
5. Lower Mantle10–100km200–500°CLight: NO · Donors: H₂(radiolysis), Fe²⁺
6. Core Interface>100km500–1200°CLight: NO · Radiation: HIGH (decay) · Fe³⁺/metallic Fe

Win Condition — ALL must be achieved before Catastrophe Deck exhausted:

  1. Closed Carbon Cycle: autotroph + heterotroph both active
  2. Closed Nitrogen Cycle: nitrogen fixer + denitrifier both active; N tokens never reach 0
  3. Closed Sulfur Cycle: sulfur oxidizer + sulfur reducer both active
  4. Closed Iron Cycle: iron oxidizer + iron reducer both active
  5. Energy Self-Sufficiency: total production exceeds consumption for 3 consecutive turns
  6. Multi-Zone Colonization: ≥3 of 6 zones with at least 1 viable organism
  7. Redundancy Check: no single organism, if removed, breaks more than 1 cycle

Mechanical Failure Modes

FailureTriggerEffectReal Event
Nitrogen CrashAll N-fixers die; N tokens → 0All organisms lose 1 BP/turn. Within 3 turns, all die.If nitrogenase disappeared from Earth, biosphere collapses within one generation
Oxygen Poisoning>5 O₂ tokens in a zoneAll strict anaerobes in that zone die immediatelyGreat Oxidation Event, 2.4 Ga — cyanobacteria almost destroyed all anaerobic life
Sulfide Poisoning>5 H₂S tokens in a zoneAll aerobic organisms take 2 Stress/turnPermian-Triassic "Great Dying," 252 Ma — euxinic oceans killed 90% of species
Thermodynamic DeathTotal energy production = 0 for 2 turnsImmediate game overFundamental: life requires continuous energy input

Difficulty Settings

ModeModifications
BeginnerRemove 8 most destructive Catastrophe cards; N-fixers are free to deploy; no Redundancy Check
StandardFull rules as written
Hard (Hadean)+5 "Hadean" events; starting resources -50%; 4 zones start with no electron acceptors
Nightmare (Titan)Hard + surface zone has hydrocarbon lakes (no water); no phototrophs allowed; must colonize ALL 6 zones

13. Tournament Format

Draft: "Primordial Soup"

Pool of 180 cards in packs of 10. Serpentine draft (pass left, then right, then left). Build 20-organism + 5-equipment deck from your 30-card pool.

Draft Tier List

TierCardWhy
SDesulforudis audaxviator4 BP/turn, needs nothing, no partners required
SCable BacteriaCross-zone syntrophy is the only cross-zone mechanic in base game
SMelanin RadiotrophTurns the most punishing events into advantages
SCyanobacterial Mat FormationEnables the oxic/anoxic dual-zone board state — best formation in game
AAny nitrogen fixerN is the bottleneck; N-fixer is mandatory infrastructure
AIron oxidizer + reducer pairInstant +5 BP/turn cycle if you get both
AANME Consortium+4 BP syntrophic bonus, highest paired bonus in game
BCommon sulfate reducersReliable 2 BP/turn in any anoxic zone
BSpore-forming organismsSurvive nearly all destructive events
DStrict aerobes (no backup acceptor)One Impact Winter or O₂ depletion shuts them off entirely

Constructed: "Biome Builder"

Deck rules: Exactly 20 organisms + up to 5 equipment. Must include organisms from ≥2 suits. Must include ≥1 autotroph. Must include ≥1 organism producing each of: Energy, Carbon, Electrons. Must be able to close ≥1 biogeochemical cycle in theory. Max 2 copies of any card. 5-card sideboard.

Ban List

CardStatusReason
Dark Biosphere Awakening🚫 BannedBypasses Viability Checks — breaks core mechanic
Synthetic Minimal Genome🚫 BannedCreates custom organism with any 3 abilities — eliminates need for syntrophic partners
Radiodurans Genesis (variant)🚫 BannedRadiation immune + sporulation + DNA repair = literally unkillable, no counterplay
Cable Bacteria⚠️ Restricted (max 1)Cross-zone syntrophy balanced at 1, oppressive at 2
Desulforudis audaxviator⚠️ Restricted (max 1)4 BP/turn self-sufficient; 1 copy is answerable, 2 is a guaranteed win condition

Rating System: ELOX (Extremophile Elo Exchange)

RatingTierTitle
2200+Archaea GrandmasterProgenitor
2000–2199MasterExtremophile
1800–1999DiamondChemolithotroph
1600–1799PlatinumSyntrophist
1400–1599GoldMetabolist
1200–1399SilverColonizer
1000–1199BronzeFermenter
<1000IronSpore

Championship: "The Deep Biosphere Open"

14. Manufacturing & Kickstarter

Manufacturing Cost

Run SizeCost/UnitRetailNotes
500 units$18.10$54.99Kickstarter fulfillment
5,000 units$9.85$54.99Distributor margin: $17.65/unit

Cardstock: 330gsm blue-core, linen finish, matte varnish. Tarot size (70×120mm) for information density. Iron tokens: real metal cubes (weighted). Electron tokens: translucent blue acrylic crystals.

$25,000
Kickstarter funding goal (500 units + art + design + video)

Realistic projection: ~300% ($75,000) based on comparable: Genotype (600%), Photosynthesis (900%), Wingspan (2700%)

Stretch Goals

AmountUnlock
$25,000Base game funded
$35,000Metal iron tokens upgraded (knurled, Fe-stamped)
$50,000Linen finish all cards
$75,000Planet Board (AXIS mode) included free
$100,00020 additional Organism Cards (community vote)
$150,000Expansion 1 "Archaean Eon" bundled for Biosphere tier+
$200,000Educator Kit add-on ($15): posters + worksheets + curriculum files

Pledge Tiers

TierPriceContents
Spore$5Digital rulebook + 30-card print-and-play
Extremophile$50Full base game
Biosphere$75Base game + AXIS planet boards for Mars/Europa/Enceladus/Titan
Progenitor$125Biosphere tier + name a card (your name in flavor text) + signed rulebook
Gaia Class$500All above + design a custom Legendary organism with the science team (4 slots)

15. Edge Case FAQ

Q: Can I place a strict anaerobe in a zone that has O₂ tokens?
No. You must first remove the O₂ (via aerobic organisms consuming it) or play an "Anoxic Microenvironment" equipment card.
Q: What happens when a zone runs out of electron acceptors?
Organisms requiring those acceptors produce nothing and gain 1 Stress/turn. Methanogens can still function (CO₂ is always present as trace acceptor). Fermenters can still function (internal electron acceptors).
Q: Can I form a syntrophic pair with an opponent's organism?
Only in shared zones, with both players' agreement. BP bonus is split evenly (round down). Either player can break the link at the start of their turn.
Q: When a Phage Attack kills an organism, does it produce resources one last time?
No. Death is instant. However, the dead organism releases 2 Carbon tokens to the zone (cell lysis releases organic matter — real biology).
Q: Can the Cable Bacteria card really link across zones?
Yes. Cable bacteria (Candidatus Electrothrix) form centimeter-long filaments that transport electrons across redox boundaries. The card can form a syntrophic link with an organism in an adjacent zone. Biologically accurate.
Q: Can I play more than one Equipment card per turn?
Yes, but each costs 1 action (you get 2 actions per turn).
Q: If I close two overlapping cycles, do I score both?
Yes. Each distinct cycle (+5 BP) scores independently even if they share a zone. An organism doing "double duty" in two cycles is metabolically realistic and scores both.
Q: What if no organisms can survive in any remaining zones?
Extinction Event — game ends immediately. Player with most BP wins. If all players have 0: everyone loses. Life failed. It happens.
Q: What does the Redox Cascade Marker actually do?
It tracks the current dominant terminal electron acceptor in shared zones, providing a visual reference for which organisms are currently viable and which are being outcompeted. When O₂ is consumed, the marker moves from "Oxic" → "Nitrate" → "Iron/Manganese" → "Sulfate" → "Methanogenic." This is the real sequence of electron acceptor depletion in any anoxic environment.

16. Scientific Glossary

TermGame DefinitionReal Science
AutotrophOrganism that produces its own organic carbon from CO₂Same
HeterotrophConsumes organic carbon produced by othersSame
ChemolithotrophGets energy from inorganic chemical reactionsSame
SyntrophyTwo organisms that depend on each other's waste productsObligate mutualistic metabolism where one partner's waste makes the other's reaction thermodynamically favorable
Redox potential (E°')Number on Electron Tower determining dominanceStandard reduction potential at pH 7, 25°C
ExtremophileOrganism with special environmental resistancesOrganism that REQUIRES extreme conditions for optimal growth (not just tolerates)
Horizontal Gene TransferMechanic for stealing/sharing abilitiesReal process of DNA transfer between unrelated organisms — bacteria do this constantly
CRISPREquipment card for modifying organismsBacterial immune system repurposed as a gene editing tool
BiofilmFormation granting Event resistanceCommunity of microorganisms attached to a surface in a self-produced matrix
Electron TowerRedox potential ranking — determines competitive exclusionThe thermodynamic hierarchy of terminal electron acceptors that determines which organisms dominate in any given environment
ΔGEnergy released/consumed per reaction (determines if a card can function)Gibbs free energy change — negative = spontaneous and energy-releasing
Syntrophic windowThe narrow conditions where a card pair can function togetherThe specific H₂ partial pressure range (often <10⁻⁴ atm) where syntrophic reactions become thermodynamically favorable

ELEMENT × EXTREMOPHILE — v1.0

"Every combo is real. Every failure teaches. Every victory is a biosphere."

2–4 players · 30–60 minutes · Ages 14+
See organisms.html for the complete 120-card organism database.
See index.html for printable card sheets.