A Turn-based Strategy game in a futuristic global cold war from the award-winning creators of Out There. Recruit a squad of special agents and run your intel agency to secure the control of the singularity.
All Reviews:
Mostly Positive (183) - 78% of the 183 user reviews for this game are positive.
Release Date:
Apr 18, 2019

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Early Access Game

Get instant access and start playing; get involved with this game as it develops.

Note: This Early Access game is not complete and may or may not change further. If you are not excited to play this game in its current state, then you should wait to see if the game progresses further in development. Learn more

What the developers have to say:

Why Early Access?

“Sigma Theory is a strategy and spy game with many emergent situations. Completing the development with the community will allow us to deepen and balance the gameplay and take the game to places we would not otherwise have planned.”

Approximately how long will this game be in Early Access?

“The Early Access will run for 3 to 6 months.”

How is the full version planned to differ from the Early Access version?

“In addition to the community's suggestions, we're planning new contents and features: 'Story' mode for each playable countries, additional agents and NPCs, new types of exfiltration missions and more exciting stuff that will be unveiled during the Early Access.”

What is the current state of the Early Access version?

“All the features in the 'About This' section are available.”

Will the game be priced differently during and after Early Access?

“The price will be raised at the end of Early Access.”

How are you planning on involving the Community in your development process?

“We are constantly in touch with the community via the Steam forum or the dedicated Discord server, run by the dev team.”
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Buy Sigma Theory - Deluxe Edition

Includes 2 items: Sigma Theory, Sigma Theory - Soundtrack


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Includes 2 items: Out There: Ω Edition, Sigma Theory


Recent updates View all (24)

May 10

Sigma Theory Early Access update 0.16.3

Dear agents, here’s update 0.16.3, featuring balancing, bug fixing and community requested changes (and a bit of eye candy too).

In this update, we continued our effort to balance the Diplomacy, and make it less easier to acquire scientists. Our goal is to progressively move the meta toward the exfiltration as the main solution to get scientists as it was originally intended. This will ramp up the overall difficulty of the game and make Strength based agents more useful. We will listen to your feedback and continue to tweak the diplomacy mechanics in future updates if needed.

Each country now has a unique color flavors during exfiltrations to add variety.
We’ve also added new and shiny Soviet buildings that you’ll discover during your missions in Russia.

Quality of life
As widely requested, there is now an option to skip the dialogue animations entirely.
For exotic resolutions, you can now resize the game window to fit your screen accordingly.

Full patchnote
---- Version 0.16.3 ----

  • Offering your gratitude during diplomatic meetings now decreases the trust gauge as originally intended
  • Decreased chances of success when asking for a scientist during diplomatic meetings
  • Fixed various gameplay issues when a country is eliminated: war with those countries is now instantly ended, missions from organisations are cancelled, arrest warrants are removed ...
  • Russia now has some typically Russian buildings in exfiltration missions
  • Different camera filters are now applied in exfiltration mission according to which country it takes place in
  • Added various UI improvements and feedbacks
  • Improved exfiltration loading time
  • Added a visual effect when a branch of the final project is completed, allowing player to see if there are a few missing percents on a slot
  • Added an option to speed up dialogues

  • Fixed bug where the first captured agent could be killed by an event during the same turn, preventing the player from completing the counterespionage tutorial
  • Fixed bug where it was possible to drag the drone on an inactive (and invisible) conflict zone, resulting in unpredictable behaviors
  • Fixed bug where drones weren't given back to the player when they should
  • Authorization by hierarchy to use drones or not is only checked once a turn, preventing various bugs
  • Fixed bug where menus and tooltips weren't properly hidden in some resolutions, leading to a game blocked in the case of menus
  • Fixed occasional freeze when using Mentalis technology for yourself
  • Fixed bug where the game tries to open a conflict zone when all active countries already have an active conflict zone, creating a wide range of problems down the road, like agents not being able to finish their action
2 comments Read more

May 2

Sigma Theory update

Dear agents, here are the main changes for patch

Bug fixes
  • Fixed bug where Braincase and Force 1 traits didn't do anything
  • Fixed bug where leader of a terrorist organisation was still shown as a target after being captured
  • Fixed bug where hackers could report that they got all information on scientists when they only got locations
  • Skip intro scene
  • Fixed drones displaying bug when one of them is faster due to a lobby reward
  • Fixed tutorial bug when agent quitted in the same turn that it was needed for a tutorial
  • Fixed bug when steam is not correctly launched
  • Fixed bug where it was possible to keep pressing the same choice button when unlocking a technology to get the result several times
  • Fixed possible data corruption when a scientist dies
  • Fixed loading bug when coming back from an exfiltration after making contact with a scientist mole
  • Fixed UI lock that could occur when hovering a busy agent right after a free one
  • Fixed bug when two agents, one of which has Businessman trait, travel to the same place
  • Fixed crash when Islamic Alliance showed up at the same turn than the first randomly opened conflict zone
  • Fixed bug where scientist menu refused to close if player happened to over a country during closing

  • Adding feedback when taking a new contract
  • Character names are now translated
  • Added "Sigma Division" marker around player country
  • Diplomacy is now a little bit harder and only previously identified scientists can be exchanged
3 comments Read more
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“The world needs more games from the creators of Out There.”
Rock Paper Shotgun

“It’s definitely a cool, layered title that has me interested in more.”
Air Entertainment

“If you like board game strategy and micro-management this is completely a game for you.”
That Video Game Blog

About This Game


From the creators of the award-winning sci-fi game Out There...

In the near future, a paradigm-shifting scientific discovery looms over the world, promising radical new technologies. The world’s superpowers realize they could have the power to destroy the global financial system, wipe out entire countries or even gain access to immortality.

However, this discovery — called “The Sigma Theory” — can only be harnessed by a handful of scientists. You are placed at the head of your country’s Sigma division. Your objective is to ensure that it is your nation that reaps the benefits of Sigma Theory before anyone else.

To achieve this you will have powerful resources at your disposal: a cadre of the world’s most elite covert agents, advanced tactical drones and, of course, your own skills in diplomacy and subterfuge.

It’s a cold war out there, one in which mankind must face up to its future.


Turn-based espionage: Use your special agents to dominate the world. Seduction, blackmail, manipulation, industrial espionage… Every low blow is both permitted and encouraged.
Dynamic narrative: Develop and manage your relations with over 100 NPCs: lobbies, armed groups, politicians… Alliance, deception or assassination, you choose.
Field operations: Direct the kidnapping of your targets during gripping pursuits through the world’s greatest cities. Discretion or direct confrontation, your agent’s life is in your hands.

First, recruit a team of four special agents from 50 unique unlockable characters to support your missions. Each comes with their own story, motivations and traits that define their behavior during missions.
Access the investigator, soldier, hacker, seducer and other archetypes to complete your Sigma division and execute your strategy.

When your team is ready, assign them missions around the world to gather scientists, discover compromising documents on local politicians, and more.
Exploit your agents’ abilities to seduce, manipulate and bribe your targets over to your side or have them neutralized.

Other nations will also use their agents to infiltrate your country and seize your scientists. Track, capture and interrogate them to gain information on your enemies, then exchange them for ransom when they are no longer useful.

Order your agents to exfiltrate scientists recruited to your cause during gripping turn-based exfiltration phases through the world’s greatest capitals. Choose the position your drones wisely to support these delicate missions.

In Sigma Theory, diplomacy is the key to achieving your goals. Meet your foreign counterparts and further your objectives using flattery, threats or blackmail. You can also recover your captured agents, advance your research, and much more. Develop your relations with powerful lobbies and armed and influential groups to obtain their favor. But be careful, they may turn on you.

Tech Tree
Sigma Theory is the cause of this cold war. Rally scientists from around the world to your cause to discover new technologies to gain the edge and change the world. Mind control, destabilization of the world economy, robot soldiers, immortality… Will you keep these discoveries for yourself or share them with the world?

Games that inspired us:

XCom, Phantom Doctrine, Plague Inc, Pandemic (board game), Rocket Ranger, Tropico, Armello, Civilization, curious expedition and so much more

System Requirements

Mac OS X
SteamOS + Linux
    • OS: Windows Vista
    • Processor: 1,3 GHz CPU
    • Memory: 1 GB RAM
    • Graphics: NVIDIA GT 440 or AMD Radeon HD 5550 w/ 512 MB
    • Storage: 1 GB available space
    • OS: Microsoft® Windows® 7
    • Processor: Dual-core 2Ghz CPU
    • Memory: 2 GB RAM
    • Graphics: DirectX® 10 compliant graphics card
    • Storage: 1 GB available space
    • OS: Mac OS X 10.7
    • Processor: Dual Core 2Ghz
    • Memory: 2 GB RAM
    • Graphics: Hardware Accelerated Graphics with dedicated memory
    • Storage: 500 MB available space
    • OS: Ubuntu 12.04+
    • Processor: 1,3 GHz CPU
    • Memory: 2 GB RAM
    • Storage: 1 GB available space
    • OS: Ubuntu 12.04+ Desktop only
    • Processor: Dual-core 2Ghz CPU
    • Memory: 4 GB RAM
    • Storage: 2 GB available space

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