Grey Goo is a real-time strategy (RTS) game that combines classic strategy mechanics and a balanced combat system with an emphasis on large-scale decision-making.
User reviews:
Mixed (15 reviews) - 66% of the 15 user reviews in the last 30 days are positive.
Mixed (2,184 reviews) - 69% of the 2,184 user reviews for this game are positive.
Release Date: Jan 23, 2015

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Buy Grey Goo Definitive Edition

Includes 3 items: Grey Goo, Grey Goo - Emergence Campaign, Grey Goo - Soundtrack


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June 23


The Steam Summer Sale is here! Buy the Grey Goo Definitive Edition for $10.16 and get the game, Emergence DLC and the complete soundtrack.

It’s the perfect time to join the battle, and a perfect chance to get your hands on some Grey Goo Swag! Head over to our Twitter account account and get involved!

For a full list of details on the Grey Goo Twitter contest please visit our forums

3 comments Read more

April 28

Grey Goo Archives - The Valiant Project

The Valiant Project was a multi-university research and development program to advance human/computer interactions. Blending disciplines from behavior-based robotics and early childhood development the project aimed to produce, high functioning machines capable of judgement in uncertainty, or System One thinking.


As the project matured, the ‘students’ as they were called spent more and more time interacting with children comparable to their mental capacity. At both the University of Edinburgh and Yonsei University, the children were often visitors from nearby children's homes.

While the ‘students’ at Texas A&M interacted almost exclusively with Aggies, all the programs eventually earned the nickname of Orphanage.


The first machines produced from the program were placed in high-risk environments demanding quick decision-making.

A Valiant Commander, Singleton is a relic from Humanity’s warring past, escorting Lucy Tak's expedition to appease concerns back on Earth. When unanticipated threats emerge, Singleton proves to be Lucy’s most trusted advisor on the battlefield.

Singleton is one of the earliest graduates of the Valiant Program, a program dedicated to creating high-functioning machines capable of making quick judgment in uncertain situations. Instantiated in the late 21st Century, Singleton served as a soldier for two centuries before being decommissioned for a third. Singleton continues to compile his one line of code.

Including Singleton, the other Valiants served in four classes:
  • Paladins (marines/soldiers)
  • Cavaliers (pilots)
  • Dragonslayers (firefighters)
  • Corsairs (deep divers)
All were considered Valiants. Inscribed on their forearm is a single line of code:

“That others may live.”

Learn more about the Grey Goo universe at Stay tuned over the next couple of weeks for more lore about the Valiant Project!

9 comments Read more


“What I can say now is that Grey Goo is a superb, cheerfully inviting real-time strategy game. It’s one I can recommend to both fans of the genre and people who have felt shut-out from RTS gaming these past few years.”

“Grey Goo understands why old-school RTS games were so much fun, and it’s a great expression of that classic design.”
PC Gamer

“Grey Goo is likely the best traditional RTS not made by Blizzard in the past five years.”

About This Game


Out of the ashes of war, a tentative truce emerges between the Humans, Beta and the Goo—but peace doesn’t last long. Ecosystem Nine finds itself thrust into turmoil once again with the arrival of a destructive, alien life form known as the Shroud.

Grey Goo is a real-time strategy (RTS) game that combines classic strategy mechanics and a balanced combat system with an emphasis on large-scale decision-making. It puts you at the center of a tactical struggle for survival—and ultimately, control of Ecosystem 9.

Take on the single-player campaign to command three factions: the Humans, masters of defensive architecture; the Beta, a proud, versatile alien race; and the Goo, an enigmatic, highly mobile life form. Or compete with any of the four multiplayer factions—including the disruptive, unpredictable Shroud.


  • Fight—or play as—the Shroud, a brand-new, multiplayer faction.
  • Command new units: the Humans’ Valiant, the Beta’s Squall and the Goo’s Siphon.
  • Explore an additional story arc with “Grey Goo: Emergence,” and discover the Goo’s true intentions.
  • Take on the Shroud in Mission 16, “Herald of Silence."
  • Sharpen your battlefield tactics in the single-player campaign, or join the fray on Steam.
  • Join the fray on Steam and find opponents through skill-based matchmaking.
  • Change the rules of the battlefield with unit-altering tech upgrades.
  • Deliver devastating blows by constructing game-ending Epic units.
  • Take the battle offline via Local Area Network play.
  • Enhance your competitive edge with Replay Mode and Observer Mode.
  • Use the Map Editor to create your own battlefields and share them with the community via Steam Workshop.

System Requirements

    • OS: 32-bit Windows 7
    • Processor: 3.5 GHz Intel Core i3 Dual Core or equivalent
    • Memory: 4 GB RAM
    • Graphics: 1024 MB DirectX 11 capable video card (GeForce GTX 460 or AMD Radeon HD 5870)
    • DirectX: Version 11
    • Network: Broadband Internet connection
    • Storage: 15 GB available space
    • OS: 64-bit Windows 7
    • Processor: 3 GHz Intel Core i5 Quad Core or equivalent
    • Memory: 8 GB RAM
    • Graphics: 1024 MB Direct3D 11 capable video card (GeForce GTX 570 or AMD Radeon HD 7870)
    • DirectX: Version 11
    • Network: Broadband Internet connection
    • Storage: 15 GB available space
Customer reviews
Customer Review system updated Sept. 2016! Learn more
Mixed (15 reviews)
Mixed (2,184 reviews)
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1,600 reviews match the filters above ( Mixed)
Most Helpful Reviews  In the past 30 days
5 of 6 people (83%) found this review helpful
64.2 hrs on record
Posted: September 23
This game is completely underrated. Unfortunately there are rarely if ever any custom steam matches to play on MP. But have a friend buy it also and you can have loads of fun together. The campaign is very solid also with the expansion. The audio and visual aspects of the game are equally stunning. For all the negative reviewers, all I can say is what were you expecting? Its very similar to C&C games on purpose. It's sort of a mix between C&C and Starcraft. There are four races, and each one is entirely unique in the way that units and structures are built, upgraded, etc. Similar to Starcraft in that sense but even moreso in my opinion. The only real complaint I have about this game is that there is basically no tutorial whatsoever, LOL. You have to learn by playing. I did notice under the Extras section of the menu it does have an encyclopedia which probably gives you more of an idea how to play with each race. A little too late now, but oh well. If you are not sure about this game but are an RTS and/or sci-fi fan, be it Starcraft, C&C, whatever, buy it. You wont regret it. I bought it for $9 on a Steam sale and it was WELL worth the money. I was really surprised to see the original price was only $39.99. The game is very well made and superbly polished. There are a good bit of cutom maps on the workshop too which adds to replayability. Also the AI is really good in my opinion. And the difficulty levels are "Insane"!
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1 of 2 people (50%) found this review helpful
11.7 hrs on record
Posted: September 22
This is a solid, very traditional RTS that's an obvious throwback to the better Command & Conquer titles (especially C&C 3). I haven't tried multiplayer (I suspect not many people are playing), but the campaigns are varied, fun, and interesting.

To be honest, I have no idea why the reviews are so mixed. Grey Goo is very polished and I would recommend it to anyone looking for a modern RTS. I've enjoyed my time with it a great deal. I guess RTS fans are hard to please.
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1 of 2 people (50%) found this review helpful
1.4 hrs on record
Posted: September 24
Product received for free
Better than expected!

Free (for me :p)
High quality cinematics
Strong, challenging campaign & AI
Amazing for Sci-Fi fans!
4 unique races to change gameplay

Multiplayer lacking (hard to match up/could use more modes)
No real tutorial (takes time to get the proper hang of things)

Solid game for sure if you're a fan of RTS or Sci-Fi genre. If you read the comments about Starcraft or C&C being superior and are a fanboy then play Starcraft. No one is forcing you're arm here :p

Look up a few guides to learn the races, get a proper tutorial if you'd prefer or just jump right in! Better with friends due to the multiplayer issues, but still viable either way! If you find this game on sale, go ahead and pick it up for sure!
Have a nice day <3
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2 of 4 people (50%) found this review helpful
11.3 hrs on record
Posted: September 20
Excellent, Good RTS in the old style, but wiht new gameplay. Each race is different, not just a copy of the other one. A good one for RTS fans!
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1 of 2 people (50%) found this review helpful
Not Recommended
5.7 hrs on record
Posted: September 25
Single player.. "connection lost??"
Apparently this issue has never been fixed from 2015 - 2016
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3 of 7 people (43%) found this review helpful
3 people found this review funny
Not Recommended
3.8 hrs on record
Posted: September 27
the game is awful. i had not played the game in a while after i got it. it took me 5 minutes in a game to rember why, the ai is bull withing 3 minutes of starting a round i was being swormed by enemy units, i had bearly built a refinery and the ai already has advanced units. i would also like to mention i had set the ai to easy and passive, my only guess is that when the ai is set to hard and militaristic, moment you start the game you are already surrondered by end game units. and the ai kept pumping them out faster than i could destroy them. so if the developers ever read this i want to know how the ai can start at the same point i am and with in 3 mins be swarming my camp with advanced tank units from the other side of the map. this game isn't worth the money even if it was free. your money would be better spent on going to trump universty.
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3 of 10 people (30%) found this review helpful
Not Recommended
1.0 hrs on record
Posted: September 21
Product received for free
Very nice idea, with subtle twists on the classic RTS. But sadly, I just found the game complicated and not griping. Lots of points for trying though.
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Most Helpful Reviews  Overall
1,097 of 1,169 people (94%) found this review helpful
44 people found this review funny
194.3 hrs on record
Posted: January 23, 2015
Click here for the video.

Grey Goo is a new RTS from Petroglyph Games that removes unnecessary micro and brings back the classic gameplay you may remember from Command & Conquer's glory days.

  • Interesting and varied, asymmetrical factions. There truly is something for every play style here.
  • The tech system limits the player in a good way, giving weight to your choice of tech upgrades without shutting you off from other options permanently.
  • Presentation: Animations, sound FX, voice acting and cutscenes are all superbly polished. While it's not the most high-fidelity game ever made it does look very nice as a whole. Even on the lowest graphical settings the game doesn't look muddy or outdated.
  • The map editor ships with the game at launch, opening up a potentially infinite amount of map variation for the future.
  • The eight maps that ship with the game are, for the most part, asymmetrical, well designed and feel balanced. It feels great playing on non-mirrored maps for once.
  • The campaign and story are above average for an RTS game. The story is supremely compelling with fantastically animated cutscenes (the best I've ever seen) and the campaign offers subtle, interesting variations on the skirmish gameplay through fifteen lengthy missions. It will likely take you a couple of days to complete the campaign and some of the later mission are quite challenging indeed.

  • Performance: The frame-rate drops with large amounts of units and structures on screen and towards the end of longer matches. Adjusting the graphics options does very little to alleviate this.
  • Only eight maps are available at launch, five 1v1 and three 2v2. I imagine they'll be adding more in the future, but I can't be sure of that at this point.

    What you need to know
  • The game doesn't ship with replay or observer mode features, but they have been confirmed for a post-launch update.
  • Grey Goo doesn't play like StarCraft and thus you shouldn't play it as such. Understand and accept this and you'll be happier for it.
  • If you enjoyed Command & Conquer 3 you'll likely find something to enjoy in Grey Goo.
  • The game supports competitive play with ranked 1v1 and 2v2 matches along with a leaderboard for each.
  • Custom 1v3, 1v1v2 and Free For All games are also supported. The max number of players on a map is currently four.

    Grey Goo is a solid old school style RTS. It has some interesting new ideas and brings back much missed old ones too. It seems that Petroglyph Games has tried to cater to the single and multiplayer communities with Grey Goo; this perhaps coupled with a shorter development time has led the game to feel as if it lacks content in certain areas. That being said, the game doesn't feel unfinished by any stretch of the imagination, though it could use an expansion or a few updates here and there to fatten it up a bit (this is almost guaranteed considering the cliffhanger at the end of the campaign). Grey Goo is a solid and polished foundation for a potentially great RTS.

    For more Grey Goo and other exciting content check out my YouTube channel, The Roleplay Gamer.
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922 of 1,024 people (90%) found this review helpful
300 people found this review funny
27.9 hrs on record
Posted: June 19, 2015
You mean that I can actually build bases?
You mean that you actually need a refinery and silos for your weird alien resource thing?

Where is all the "new and innovative" complete lack of basebuilding and resource gathering? Why am I not restricted to the "rapid-pace action" of a 50 population cap?

This game clearly has no idea how to appeal to the action-craving youth of today, it totally lacks innovation and insight into what the gamers WANT! EA would never make anything so disconnected like this..... AND THAT IS WHY IT IS ABSOLUTELY ♥♥♥♥ING AMAZING.

Please, thank you, yes. I am so sick of idiots trying to "fix" the core components of RTSes that make them fun in the first place and producing horrid games like CC4. Grey Goo intelligently keeps all the core elements of a truly fun RTS experience but still expands on them in completely unique ways such as with the Goo faction and the mechanics of the Beta and human basebuilding systems. Basically, I've been a hardcore CC fan all my life until EA gutted it and murdered my dreams. Luckily, Grey Goo has stepped up to fill that void.
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336 of 356 people (94%) found this review helpful
191 people found this review funny
42.3 hrs on record
Posted: May 28
If RTS games were cans of beans, Grey Goo would be a generic store brand can of beans.

If you tend to like canned beans in general, there is a decent statistical likelihood that you will probably like this particular can about as much as usual.

If you don't care for canned beans or already have a favorite brand, the likelihood of you being impressed by this particular can are shall we say low.

Personally I'm not a huge fan of canned beans. But every now and then they can be ok. This can was ok too.
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Recently Posted
22.5 hrs
Posted: October 17
Grey Goo is a blander, kind of budget Starcraft. It has innovative base building and unit mechanics between it's three (initial) very diverse factions and much of the polish, too, with great CGI cinematics and a a raft of relatively 'hard' (i.e. plausible) sci-fi pretensions. But gameplay just lacks excitement somehow.

It has novelty, but in the context of obvious derivative echos: the aliens are junky, lower tech (like the Terrans), with South African sounding accents and are more sympathetic that the human faction, with a colder, clinical aesthetic, touting smoothly curved hovering units (echoing the Protos). Their structures need unbroken adjacent conduit connection to the core base building to operate, which is interestingly different.

The titular Goo would be the obvious Zerg swarm stand in. They're unique in having no base structures to build, all splitting off bigger mother blobs that harvest resources directly.

But as a core concept they're emblematic of the game's lack of pizazz. Fundamentally problematic to work with artistically: typically, the 'grey goo' concept involves out-of-control nano-bots that consume all matter around them, reducing entire planets to a mush of their replicas. Nightmarish and unstoppable.

But of course, to fit the RTS genre there needs to be units of some kind to click on and control. So the game goes half way and has undulating grey pancake things and specialised bug-eyed offspring for most offense unit that look kind of arbitrary and ridiculous. It all feels a little too naff, that they can't munch on trees and scenery, or even enemy units all the much, since the game has to be somewhat balanced and playable.

The story ark was ok, but predictable and uninspiring for me as a hard sci-fi aficionado. They make use of a fair bit of real world terminology (e.g. Von Neumann probes, etc), as well as genre tropes, which is cool to get it out there, but kind of trite.

I can't comment on multi-player, which I didn't really try, with no friends owning the game to play with and little enthusiasm after the single player.

By the time I'd completed the main campaign and Emergence DLC I was just glad I'd made it to the end! I struggled a lot with the final missions, not really in a fun way. Although they were presumably meant to crescendo, I had to check out multiple YouTube videos, use save games prodigiously and really take a lot of time sitting around to make sure my Goo forces were built up to max strength before attacking, etc.

Overall, if you're an RTS fan then you could do worst than grabbing this while it's on sale. Far more artistic value than Ashes of the Singularity, for example, and slightly better money's worth, with an extra DLC mission and forth faction added on for free earlier this year. So, check it out, why not. :-)
Helpful? Yes No Funny
1.0 hrs
Posted: October 15
its terrible
Helpful? Yes No Funny
39.7 hrs
Posted: October 12
Great game with a sci-fi element.
Easy to use to start building your army and fight.
Helpful? Yes No Funny
Daddy Warbucks
19.8 hrs
Posted: October 10
Its no StarCraft or Coh strat wise but that does not mean this game could get there. It is spinning and odd web bewtween total anhilaiiton and starcraft. The plot is there but the xeno enemies are original but the gameplay istelf is underwhelming.
Helpful? Yes No Funny
Gustavo Fring
0.5 hrs
Posted: October 10
it's dumb.
Helpful? Yes No Funny
0.5 hrs
Posted: October 9
Grey Goo just makes me angry.

Angry that EA destroyed Command & Conquer and Westwood Studios. Had that not happened, Grey Goo wouldn't exist to disappoint me.
Helpful? Yes No Funny
111.5 hrs
Posted: October 7
I am simple player and like this game. It is not too complicated. Just a right mix of elements. Many hours of fun. Not sure why there are not many good reviews.
Helpful? Yes No Funny
15.2 hrs
Posted: October 7
good game
Helpful? Yes No Funny
5.4 hrs
Posted: October 5
I feel nothing when playing this game, literally nothing. Just moving the cursor around, defeating opponents and that is it. I'll stick to C&C Red Alert 1.
Helpful? Yes No Funny
2.8 hrs
Posted: October 4
Really really good so far , graphics are good gameplay is good and its runs really smooth
Helpful? Yes No Funny