
- BGG rank
- BGG #968
- BGG rating
- 7.5
CO₂: Second Chance
- 1–4 players
- 60–120 min
- Complexity 4.1/5
- 2018

Rules assistance for On Mars: Alien Invasion
Plain-language explanations of turns, card effects and disputed situations, with official source references and saved question history.

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Answers come from the official rulebook, with the page to check.
On Mars: Alien Invasion is an expansion for On Mars released in 2022 for 1–5 players, 80–150 minutes per game, and ages 14 and up. It was designed by Vital Lacerda and its main mechanics are Cooperative Game and Worker Placement.
On Mars: Alien Invasion is the much-anticipated Somewhat Cooperative Expansion to Vital Lacerda’s best-selling and highly-rated On Mars base game. Though this expansion was originally going to be named Surviving Mars, Eagle-Gryphon Games made the decision to change the name to On Mars: Alien Invasion to better reflect the theme and content of this expansion. The game narrative is contained in four chapters of a story written by Nathan Morse. Gameplay contains four new and different ways to expand upon and play the base game. You will play one versus many; completely cooperatively; and even solo if you wish, depending on the chapter. Included are four fresh and completely replayable ways to establish colonies On Mars! For instance, here is the narrative that opens the first chapter and sets the stage for all of the following action: Alert! Sensors indicate that aliens are invading the famous red planet! Long have the conspiracy theorists predicted this. The threat to your mission is too great; you must take action. Will you be able to prevent the infectious spread of these beings bent on expanding to every habitable planet in the galaxy? Or will you play for the other side, a species trying to establish a colony on Mars, blithely oblivious to the danger their expansion represents, unaware that there are others out there eager to keep humans “where they belong” on Earth. —description from the publisher On Mars: Alien Invasion is a short story expansion to On Mars made in 4 chapters with 4 different modes of play. The short story is called Alien Invasion and contemplates the following Chapters and modes of play: Chapter 1 - Invasion - 1 vs All - 3 to 5 players Chapter 2 - Outbreak - Co-Op - 2 to 4 players Chapter 3 - Blackout - Co-Op - 2 to 4 players Chapter 4 - Monolith - Solo - 1 player —description from the designer
On Mars: Alien Invasion supports 1–5 players according to the catalogue. This range comes from the publisher’s listed player count, so the game can be set up for any group size within it. Some setups, rules and scoring details may still vary by player count, so check your edition’s rulebook for the exact configuration.
The listed playing time for On Mars: Alien Invasion is 80–150 minutes. This is the publisher’s estimate for a full game. The actual duration depends on the group, the player count and familiarity with the rules: first sessions usually run longer, while experienced groups often finish faster. Setup and teaching time are not included in this estimate.
The catalogue lists On Mars: Alien Invasion for ages 14 and up. This is the publisher’s recommendation and reflects reading demands, rule complexity and small components rather than theme alone. Younger players can often join with help from an adult, so check the age guidance on your edition and consider your group’s experience with board games.
On Mars: Alien Invasion has a complexity rating of 4.0 out of 5 from BoardGameGeek players, which makes it a heavy game. The rating reflects how much rules knowledge, planning and decision-making a typical game demands. Expect a longer first teach for heavier games, and use a preparation guide before game night.
On Mars: Alien Invasion belongs to these categories: Economic, Territory Building, and Video Game Theme. Its main mechanics are Cooperative Game and Worker Placement. Categories describe the theme and setting of a game, while mechanics describe what players actually do on their turns. Each mechanic links to a catalogue hub with similar games, which helps when you want something comparable.
The credited designers of On Mars: Alien Invasion are: Vital Lacerda. These credits come from the published game data and name the people responsible for the game’s design, not its illustrators or publishers. Designer pages on MeepleRules collect other titles by the same designers, which helps when you enjoy a game and want to find similar ones.
The catalogue lists On Mars: Alien Invasion as an expansion for On Mars. Expansions add new content, rules or scenarios to the base game and usually cannot be played on their own, so you need On Mars to use it. Check that your edition of On Mars is compatible, as some expansions were revised between editions.