Get sci-fi spy sim Sigma Theory free this weekend

A special agent superimposed on a hologram map
(Image credit: Goblinz Publishing)

GOG is giving away Sigma Theory: Global Cold War, a strategy game set in a future where global superpowers compete over technological advances by sending agents and drones around an XCOM-style hologram of the globe. It's a game of turn-based espionage that lists Tropico, Armello, Civilization, Plague Inc. and the board game Pandemic among its inspirations.

Sigma Theory was designed by Mi-Clos Studio, the creators of the Out There series, which is reflected in its regular transformations into a choose-your-own-adventure game—when you're commanding agents in the field, for instance. Each of those agents comes from a selection of 50 named spies, all with their own backstory and personality traits that influence how well they perform and suggest which course of action you should tell them to take when being chased through the streets or trying to hijack secret documents.

There's also diplomacy and research, with tech trees that might unlock hypnotic indoctrination, combat robots, accurate prediction of the stock market, alternative energy sources, or straight-up immortality. The Sigma Theory of the title is a scientific breakthrough that makes all this possible, putting the world on a fast-track to the singularity—assuming the ticking-down doomsday clock doesn't wipe us out first.

As head of one nation's Sigma division, what you choose to do with each breakthrough, whether you share it with the world or sell it to a private company or keep it for your country’s government, will influence that doomsday countdown. So maybe don't flog it all off to a guy who calls himself “"Lucky Lorenzo" and works for a cartel is what I'm saying.

You can download Sigma Theory: Global Cold War on GOG, where it's free to keep until 6am on Monday, June 19, PST. GOG is also having a summer sale at the moment, which means you can also grab games like Tangle Tower for 80% off, Outward: Definitive Edition for 75% off, Last Call BBS for 50% off, and Unpacking for 40% off.

Jody Macgregor
Weekend/AU Editor

Jody's first computer was a Commodore 64, so he remembers having to use a code wheel to play Pool of Radiance. A former music journalist who interviewed everyone from Giorgio Moroder to Trent Reznor, Jody also co-hosted Australia's first radio show about videogames, Zed Games. He's written for Rock Paper Shotgun, The Big Issue, GamesRadar, Zam, Glixel, Five Out of Ten Magazine, and Playboy.com, whose cheques with the bunny logo made for fun conversations at the bank. Jody's first article for PC Gamer was about the audio of Alien Isolation, published in 2015, and since then he's written about why Silent Hill belongs on PC, why Recettear: An Item Shop's Tale is the best fantasy shopkeeper tycoon game, and how weird Lost Ark can get. Jody edited PC Gamer Indie from 2017 to 2018, and he eventually lived up to his promise to play every Warhammer videogame.

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