A downloadable smergy for Windows and macOS



It's Mars' first day at a new school. Except every day is his first day at a new school. Every night the world ends.

Mars Underground is an apocalyptic adventure game in which the player relives the same day over and over.

The player attempts to solve the brain damaging mysteries and uncover multiple potential endings as they explore the possibilities of this time loop.

Take experimental prescription drugs. Talk to a toilet. Get hit by a car. Humiliate yourself repeatedly.

All in the name of figuring out what on earth is going on.


  • Unique time loop premise that explores the possibilities of branching stories and multiple endings in interactive fiction.
  • Game design that mixes classic adventure game conventions with sandbox-style gameplay. As the player discovers new topics and acquires new items the world opens up and they can try more things each day.
  • All original, dynamic music soundtrack.
  • Simple, easy to grasp gameplay that can be fully played with either mouse, keyboard, controller or touch input.

Explore Phobos City

  • Solve the mysteries of Phobos City and try to escape the timeloop!

  • Interact with the charming and witty citizens! Make friends!

  • Relive the same day over and over: almost as tedious as real life!

Design, Development, Programming

Matt Sanderson


Matt Sanderson

Paul McMahon (Akumenn)


Matt Beer

Vexed Enigma



Jason Perry


HimeWorks (www.himeworks.com)



Hudell (hudell.com)

Galv (galvs-scripts.com)


Jason R. Godding









Alex G: Xeliard


MarsUndergroundDemoAugust2018.zip 164 MB
Mars Underground Demo.zip 144 MB

Development log


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I realy loved this game!! I was wondering is it availible yet or is it still demo?


Thanks for making a mac version. This game looks really great


When are u going to release the full version?


Well... the plan was to have it finished and released now, in September. Unfortunately I haven't been able to make that deadline. I'm not going to announce a new release date just yet, I'm waiting until I can set a date I'll be certain to hit. I don't want to continually announce dates and then fail to meet them and I don't want to cut the game down to get it out either.



Intresting concept! I would love to do a LP of the game if you allow that. If so, do you also allow Let's Players (like myself) to use YouTube's Partner program to place ads on said video?

Hey, sorry I missed your message and am only just getting back now.

I certainly do allow ads on let's plays


I'm liking what I'm seeing so far. Best of luck with your project!


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Octopix winner and New Demo

Stunned to announce that Mars Underground won the Octopix for best independent game in the Strasbourg Festival!

Strasbourg winners

I've also just uploaded a new, improved demo:

-New tile edits by Matt Beer
-New name input screen
-New "show hotspots" button
-Added a special "demo exclusive" ending
-Fixed lots of little glitches and bugs


You guys seriously need to try the demo, it's been a hilarious ride.


Will you add linux support?


Yes, the final game will be available for Linux and Mac

Updated Demo 7-July-2016

  • Can play through the entire day!
  • More locations. More things to do. More music. More everything.
  • Can travel on bus. Reach locations: Phobos City, Pac Street, Moloch Headquarters
  • Use of Jay's VariableMix plugin for dynamic music crossfades
  • Removed icon pop-ups
  • Dialogue choices now use HMSChoiceDisplayMode

Note: HTML5 version is not compatible with itch.io and had to be removed.


Quite an interesting game, it seems like it could have alot of potential if done right.

Continuing development on this would defenently be worthet.

By the way:

I am curious about what language/software this game was developed in.

Scincerely -madK

Thanks. I'm preparing a longer demo right now. It was developed with RPG Maker MV



When is the full game going to be released

A longer demo is planned for early July. The full game will be out in 2017.


Thank you! I can't wait! 😀


This is quite a wonderful game

This looks wonderful.

Mac build please!


I'm Uploadind a Vid Of This Game

how do i get to the gym after lunch. i can't go back inside

Sounds like a bug. After lunch ends, I just walk to the door and I'm right back inside again.


Played through the demo and this is a really I like what's going on so far! I'll keep my eye on this.


I'm gonna record this game and post it on YouTube. The game is amazing and i'll also gonna review it after I played the demo. :D

Cool! Look forward to seeing what you think

The error at the start of "cycle 2" should be fixed now.

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found an error, occured immediately after playing threw the default day


looks intresting though, let me know when you fix it! I'm excited to play more!

Thanks for having a look at my game!

I'm having difficulty recreating that error. Were you playing the browser version or the download? What sort of device were you using? What is your internet connection like?


hi I was playing in browser in chrome and I have timewarner cable. After I finished the default day the error occured on the second day as I was about to get out of bed. Hope that helps.


Had Same error on day after default loop after trying to wake up, failing, clicking sleep in, then replayed the time-warp animation, game crashed a few seconds after that

Game looks awesome though! can't wait for more


yeah, this is exactly what I did!

Thanks so much to both of you for having a look!

It appears this bug crops up the first time the game is run, before an image has been cached, which is why I was having so much trouble recreating it.

Hope I can fix it quickly.

Updated 30 March 2016:

-Shortened "default cycle" by removing most of the school section

-Now using 16x16 tilesets

-All events are now triggered by "player touch"

-Graphics tweaks

-Gameplay tweaks