How to Play Terraforming Mars: Generations, Actions & Scoring
Terraforming Mars is played across a series of generations. Each generation gives players a chance to buy new project cards, take alternating actions and then produce resources. The multiplayer game ends after oxygen reaches 14%, temperature reaches +8°C and all nine ocean tiles have been placed; the highest final score wins.
Researched rules guide. Checked September 15, 2026 against FryxGames’ official base-game rules. This page covers the original Terraforming Mars board game on the Tharsis map. Expansion rules, Ares Expedition and The Dice Game are separate. No hands-on testing is claimed. Editorial standards.
On this page: Set up the base game · Follow the generation phases · Buy project cards during research · Choose one or two actions per turn · Play project cards correctly · Resolve production · Raise the global parameters · Finish the final generation · Calculate final scoring
Set up the original game using one agreed variant
Place the Tharsis board, ocean tiles, temperature marker and oxygen marker as directed by the rulebook. Each player chooses a color and takes a player board and markers.
The base rules distinguish the standard introductory setup from the Corporate Era variant. Use one setup consistently. Corporate Era changes the project deck and initial production, so do not combine its starting conditions with the standard setup by accident.
Corporations and starting project cards determine your early options. Read your corporation before buying an opening hand: a card can be powerful in general but inefficient for the specific resources, tags or discounts your corporation supports.
A normal generation has four phases
- Turn order: pass the first-player marker clockwise.
- Research: draw four project cards and decide which to buy into your hand.
- Action: players alternate turns, taking one or two actions or passing.
- Production: convert energy to heat, then gain resources from production and terraform rating.
The first generation uses the setup procedure instead of the normal turn-order and research phases. After that, repeat the full sequence until the global end condition is reached.
Buying a project card is not the same as playing it
During the Research phase, draw four project cards. You may keep any number of them, paying 3 M€ for each one you add to your hand. Discard the rest.
That payment only buys the card into your hand. To use it later, you must take a Play a Card action, meet its requirements and pay its printed cost, modified by any relevant discounts or resource substitutions.
Keeping too many cards can consume money without improving your board. There is no benefit merely for owning a large hand unless a card or milestone specifically rewards it.
Take one or two actions, or pass
During the Action phase, players take turns in order. On your turn, take one action, take two actions, or pass. If you pass, you take no more actions for the rest of that generation.
The main base-game actions are:
- Play a project card from your hand.
- Use a Standard Project.
- Claim an available Milestone you currently satisfy.
- Fund an available Award.
- Use an action printed on a blue card.
- Spend 8 plants to place a greenery tile and raise oxygen if possible.
- Spend 8 heat to raise temperature if possible.
Taking only one action can preserve timing. You are not required to take two simply because you can. That can matter when waiting to see where another player places a tile or whether a milestone remains available.
Check project-card requirements before paying
A card may require a minimum or maximum oxygen level, temperature, ocean count, production level, tag or other game state. Requirements are checked when the card is played.
Green automated cards usually provide lasting effects or production and remain face up. Blue active cards can provide ongoing effects or actions. Red event cards resolve their effects and are then placed face down, although their victory-point effects still count as specified by the scoring rules.
Steel and titanium are specialized payment resources. Steel normally helps pay for cards with the Building tag, while titanium helps pay for Space-tag cards. They do not replace M€ on unrelated project costs.
Production tracks and stored resources are different
Your player board tracks both current resources and production. Increasing a production track changes future income; it does not automatically give you that many resource cubes immediately unless the effect explicitly says so.
During the Production phase, first convert all remaining energy resources into heat. Then gain new resources according to the production tracks. M€ income also includes your current terraform rating.
Because production happens only once per generation, a production increase bought early in the Action phase usually begins paying back at the end of that generation. A late-game production increase may have very few production phases left to recover its cost.
Three global parameters control the multiplayer end
The shared terraforming targets are:
- Oxygen at 14%.
- Temperature at +8°C.
- All nine ocean tiles placed.
When you raise oxygen, raise temperature or place an ocean tile while that parameter can still advance, you normally increase your terraform rating by 1. TR is both an income component and a victory-point source.
The parameter tracks contain bonuses at specified steps. Resolve those bonuses when the corresponding step is reached. If a parameter is already complete, trying to increase it further does not continue generating TR from that parameter.
Milestones and Awards use different timing
A Milestone is claimed by taking an action when you meet its condition and paying the required cost. Only three Milestones can be claimed in the game, and each claimed Milestone is worth 5 points.
An Award is funded by taking an action and paying its current funding cost. You do not need to be leading that category when you fund it. At final scoring, the players who actually lead the funded category receive the Award points according to the rules.
Only three Awards can be funded. Because Milestones lock immediately while Awards are evaluated later, they create different strategic races.
Complete the generation after all three parameters finish
The game does not stop in the middle of the action that completes the third global parameter. Finish the current generation, including all remaining Action-phase turns and the Production phase.
After production, players receive the rulebook’s final opportunity to convert sets of 8 plants into greenery tiles in player order. These final greenery placements can still affect map scoring.
Then proceed to final scoring.
Final score starts with your terraform rating
- Terraform rating: your final TR is your starting victory-point total.
- Awards: score each funded Award.
- Milestones: each claimed Milestone is worth 5 points.
- Greenery: each owned greenery tile is worth 1 point.
- Cities: each owned city scores 1 point for every adjacent greenery tile, regardless of who owns that greenery.
- Cards: add victory points from played projects and resource cards as directed.
The player with the highest total wins. The official rules use remaining M€ as the tiebreaker.
Common Terraforming Mars rules mistakes
- Treating research cost as the card’s play cost: buying a card into your hand and playing it are separate payments.
- Taking another turn after passing: once you pass, you are finished with that generation’s Action phase.
- Confusing production with stored resources: production determines later income; cubes are what you currently own.
- Ending immediately when the third parameter finishes: complete the generation first.
- Giving a city one fixed point: cities score from adjacent greenery at the end.
Continue learning Terraforming Mars
- Terraforming Mars game guide
- Terraforming Mars strategy: card discipline, production, milestones and endgame timing
- Compare engine-building board games
Sources and scope
Checked September 15, 2026. This page covers the original Terraforming Mars board game. Expansion maps, Prelude, Colonies, Turmoil, Venus Next, Automa and standalone spinoffs can change setup or gameplay.