Oxygen Not Included

Oxygen Not Included Review: A Cozy, Engaging Puzzle of Survival

Oxygen Not Included (ONI) is a game that brilliantly balances complexity and relaxation in a way that feels both nostalgic and fresh. It reminds me of the serene-yet-strategic rhythm of old Civilization games or classic RTS titles, where every move you make feels meaningful and satisfying. From the moment you dig out your first few tiles, ONI draws you into a living, breathing world where every system—whether it’s oxygen production, temperature control, or plumbing—feeds into another, creating a delicate web of survival.

What makes ONI truly remarkable is how it keeps the stakes high without feeling stressful. Your duplicants (adorably quirky colonists) require constant care, but the game gives you the time and tools to solve each problem at your own pace. Whether you’re figuring out how to deal with polluted water or optimizing your power grid, every challenge feels like a rewarding puzzle. And yet, it’s never overwhelming; the soothing art style, cheerful duplicant animations, and quirky sound effects make even disasters feel strangely endearing.

Much like Civilization, ONI taps into that addictive “one more turn” energy, though here it’s more like “just one more cycle.” You’ll find yourself tweaking layouts, refining systems, and dreaming of the perfect base design long after you meant to log off. It’s also deeply strategic—managing resources, planning ahead for crises, and keeping your duplicants happy feels as engaging as managing armies or building wonders in Civ.

There’s also a creative freedom in ONI that echoes the best sandbox experiences. Do you want to create a sprawling, multi-level utopia with every duplicant living in perfect harmony? Or do you embrace the chaos, watching as things (inevitably) go hilariously wrong? The game doesn’t punish you for failure; instead, it encourages experimentation and learning, making every playthrough unique and personal.

If you’ve ever loved the careful planning of Civilization or the satisfying micromanagement of a classic RTS, Oxygen Not Included is a must-play. It’s a game that feels like home for strategy enthusiasts—a warm, delightful world where every challenge is as satisfying as the solution.

Definitely recommend this game for those that like to build. I've gotten pretty hooked on this. The art is very cute, but the building is really complicated. The colony are like taking care of kids. Its really hard to build a thriving colony. I have never gotten pass 15 people in my group. It was harder than I thought. I have no idea how many times I've had to restart, but it's still a good game, if you have the time to just build.

Yo this is definitely a fun game to play. Just some advice for beginners, manual generators are way better than you'd think. Get someone to power your systems during the night! Once you can get a hydrogen power system, or solar power system then you can replace all the manual generators.
Also, when your in the mid-game, <150 days, you should think about having duplicant zones, have some of them work at the center, some at the surface, and some nearby oil.

Excellent game. I cannot stop playing. great support and community out there. I highly recommend this game to anyone.

Excellently balanced game! Deeply enjoyable for a working adult, without requiring hundreds of hours to commit.

10/10 game
it gave me a superiority complex. This game is enjoyable yet very stressful at the same time. At some point I became numb to their deaths, they kinda deserved it anyways.

over 200 hours, still intimidated by rockets. 10/10

I have sunk 400+ hours into this game, several dozen colonies, and by some miracle that I'm still not entirely grasping... my current play through as of writing this has had a colony survive to 1000+ cycles. Food shortages, runaway heating, collapse of oxygen production. Been hit by it all and somehow, someway, my duplicants survive.

For the game itself, though, it has a rather well perfect difficulty. The environment itself is both a threat and bounty for the colony to tame and grow. And the greatest threat is actually you the player. Something that a lot of other colony sims don't really capitalize on. Your mistakes can sneak up on you, like placing a high heat producing structure in one area that at first seems sensible due to the low ambient temperature and then a few dozen days later and your sleeping area is being flooded out or your crops are all wilting from overheating. And then your scrambling to try and fix things, either by trying to pump heat away from an area or rebuild things in a cooler location. Or the wonderful nightmare of uncovering a volcano and having to live with the consequences of that action. And it's all handled in a way that just keeps you wanting more.

This game is very difficult but very fun, I highly recommend it.

Well, as you can see, I've put over 2400 hours into this game since 2019. I've never bought a DLC and I've never even launched a rocket if that tells you anything...maybe I'm just a serial restarter. The never seems to get old for me, even when it kicks my tail. 10/10

Easy to learn, fun and connective. excellent soundtrack. Continuous skills to be mastered. a very easy Hard Game

I watched a playthrough of this game by one of my favorite youtubers and it looked like something right up my alley. I've only played 21 hours of it so far, but it's been the best 21 hours spent. The game is a lot of fun. Granted, it is a little difficult to figure out in some aspects but I already have a lot going on and feel I haven't even scratched the surface yet! Once I get further along, I'll come back and say again if it's worth the buy still or not.

---{Graphics}---
☐ You forget what reality is
[/] Beautiful
☐ Good
☐ Decent
☐ Bad
☐ Don‘t look too long at it
☐ MS-DOS

---{Gameplay}---
[/] Very good
☐ Good
☐ It‘s just gameplay
☐ Mehh
☐ Watch paint dry instead
☐ Just don't

---{Audio}---
☐ Eargasm
[/] Very good
☐ Good
☐ Not too bad
☐ Bad
☐ I'm now deaf

---{Audience}---
[/] Kids
[/] Teens
[/] Adults
[/] All

---{PC Requirements}---
☐ Check if you can run paint
[/] Potato
[/] Decent
☐ Fast
☐ Rich boi
☐ Ask NASA if they have a spare computer

---{Difficulity}---
☐ Just press 'W'
☐ Easy
[/] Significant brain usage
[/] Easy to learn / Hard to master
☐ Difficult
☐ Dark Souls

---{Grind}---
☐ Nothing to grind
☐ Only if u care about leaderboards/ranks
☐ Isn't necessary to progress
[/] Average grind level
☐ Too much grind
☐ You‘ll need a second live for grinding

---{Story}---
☐ No Story
[/] Some lore
☐ Average
☐ Good
☐ Lovely
☐ It‘ll replace your life

---{Game Time}---
☐ Long enough for a cup of coffee
☐ Short
☐ Average
[/] Long
☐ To infinity and beyond

---{Price}---
☐ It’s free!
[/] Worth the price
☐ If u have some spare money left
☐ Not recommended
☐ You could also just burn your money

---{Bugs}---
[/] Never heard of
☐ Minor bugs
☐ Can get annoying
☐ ARK: Survival Evolved
☐ The game itself is a big terrarium for bugs

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The Pros:
+ Easy to learn, hard to master gameplay
+ Management sim at its very core! It will challenge your balancing resources.
+ Rogue-like: so every new game is a fresh start

The Cons:
- So much data and elements in it that you must have a significant percentage of nerd blood to have played this game (but then again that's the fun of exploring this game and its randomly generated worlds) 🤓

Maybe add reproduction mechanics for the duplicants? In other words let them fuck ;)

I returned this game when I first got it, I was a Don't Starve player at heart and this game is way more different than I thought it would be. I was pretty confused at first, and I left it alone for a while. Eventually a friend got me into it and eventually I passed the learning curve and I love it! The science expect is so deep and complicated its awesome.

I use this game not only as an entertainment source. but also as a way to learn basics(and not only basics) of physics and chemistry. Going through new problems and finding the way to solve them, thinking about how to fix the problem and finally realising is so great and it gives giant boost of dopamine into my brian.

Definitely late to the game in submitting this review, but if you enjoy base building games, you should look into this. It takes a certain kind of thinking to succeed and you will likely need to look up how individual machines and parts work. You are given a toolbox, very little in the way of instructions, and have to create your own solutions to problems.

I love that every time I fail, I learn valuable lessons for the next time. Sometimes, it's just learning to organize better and sometimes it's a matter of timing as crops fail or the heat of your machines over takes the base.

New players may be overwhelmed and the fact that your dupes have to do the building for you can be a strange adjustment, but overall it's a true masterpiece of base building games. At ~250 hours, I am still learning and making mistakes.

The online community is truly the star of the show. There are many thoughtful creators that show both how to build stuff AND how it works. As someone with ADHD, I need to know WHY I am doing something even if I am just "copying/pasting" a tutorial and the people that play this game are excellent, helpful humans.

Give it a shot.

a game with so many levels of engagement and creativitiy. i have logged more hour on this game than any other and i feel like i am only half way through it.

This game had many great details which made it both challenging and more realistic, which made it very fun. I just disliked the very harsh difficulty to fight global warming in the later stages of the game.

I thought this was going to be a cutesy little sim game.... Fooolish and nieave younger self.... super complex mechanics can be fun at face level but very deep sim with layers of elements to get lost in

This is an awesome game with cute art about managing a colony of embryos in teenagers bodies and i love it. About the only reason i won't be slamming loads more hours into it is because i have limited gaming time and want to spend it or at the very least play games with the option to add friends instead. But let it be assured that this game will have you forgetting what day it is

The game is quite punishing in the respect that you can get to stages where your colony is failing but you haven't yet used the tech that would fix it to know if it is worth building given its cost versus your remaining supplies of that material. This is especially true because not building well early can spell disaster later, so you're put in this difficult spot where you'll rather need to look up guides, die by making mistakes, or first discover what everything is used for in sandbox mode

However doing this and knowing these things greatly streamlines the game and people often then feel the game becomes repetitive. I have not yet experienced this myself as i have not looked things up so my colony is an open flame awaiting an inevitable spark, which it almost got earlier as my army of braindead didn't deliver coal to my power generators which killed my oxygen pumps (6% breathability :D)

For the genre of game this is, it has to easily be one if not thee best of its kind. I enjoy my time with the game, even if it might be coming to an end, and if you like resource management and the like, you will surely love this.

So complicated and simple! The variety of maps and ways to build/survive are endless. One of my favorite games of all time.

Do you love micro-managing others? Do you enjoy failing repeatedly and starting over? DO YOU LOVE WORKING WITH COMPLEX SURVIVAL MANAGING SYSTEMS?!

Damn straight you do and this is the game for you. Jokes aside, you will be trying to manage everything your little Dupes are doing, they will listen or they may not. Eventually you'll figure that out just for them to begin dying to one of the many dangers like, disease (EVERYTHING HAS GERMS!!), temperature (Too hot to grow food, too bad.), random stuff (They are indeed idiots without you...), and lack of OXYGEN! (Oxygen is not included remember...).

You will most likely start over many times after overcoming one problem only for the batch to die to a new thing you didn't factor. (Power went out? Things are getting damaged?! OH You didn't factor in how much watts your wires can handle and now the whole place is shutting down and halting everything, ya that just happened.) But that is part of the fun, going at it fresh with more experience, more knowledge, and a hope that these little bastards might survive your... cough... cough... Management style. XD

Not only that but with their unique personalities, these little dupes grow on you and all you want to do is see how long little Nisby can go from a first cycle dupe (Those who know. Know.), to exploring space and visiting other asteroids (DLC Anyone...?), to cycle 365 and patting yourself on the back for keeping these little buggers alive this long. Congrats, you earned that break.

It took myself a long time to eventually get to playing this game and I did see enough updates through time to know this game wasn't always in the current shape. Now that I've actually played it, I must say that as it currently is with DLC, this game is a blast and very addictive to play. I highly recommend it.

It was good while it lasted, overwhelming at the start but watching videos and reading the wiki you can go really far. Thanks Team Klei for this treat!

This game will consume you entirely. Simple on the surface but soon you glimpse the depths and intricacy of its astoundingly realistic mechanics and your life is over.

Beyinsiz bi avuç elemana sürekli bişeyler yaptırmak istiyosanız oyun tam sizlik

Endüstri [strike]mühendisliği [\strike] nden daha zor*

I never thought I would be so interested in a 2d game, but its amazing how in-depth this game is and how much you can do with the overlays. The modding is pretty impressive too. I really enjoy this game to just kill time or relax without thinking too much. And there are mods you can get to streamline the process so you don't have to commit so much though to the logistics. There aren't any 2d games that I have that i have more hours on. Its worth a buy.

one of the best game i ever played. amount of mods and their variety makes it impossible to run out of potencial content.

I tell you what - I love the building aspect of this game. I'm having a hard time with the survival bit. You get really great progress just to see a flaw in where you're going to want to start over. I at some point decided to cheat a bit and would refresh to oxygen with a cheatcode. Yet at some point I had too much pressure in the base and everyones morale went down for popped ear drums - I couldn't fix it.

I got as far as having 15 or so meeps. Building everyone their own apartment room complete with flushing toilet, showers, their own food table. Had gardens, plumbing figured out. I made it to where we could have pressurized chambers to start filling up tanks with different gases and almost got to the point I could kill slug germs.

I would absolutely love to someday get to the surface and see what the space exploration is all about!

GG, an addicting game that is very hard but very fun to get good at. I wuld recommend this game to people who like city builders but want to spice it up, Dont starve players and everyone who wants a challenge in this type of game.

Oxygen Not Included is an AMAZING game! I have spend soo many hours and still find it super entertaining, always looking for something new to do. The mods also add to the experience. I can't wait for a next DLC with a more "warm" kind of theme ^_^

I like:
- Good controls and game-play.
- The sound design and music is sooo engaging
- The duplicants are super cute. No matter if they are new, their personalities are endless.
- The Science aspect of the game. Making calculations has never been so fun.

I don't like:
- Game Instability. When there are too many duplicants, or just stuff happening in the map, the game crashes at times.

Masterpiece of a game. I love that every resource can be recycled and reused, and that every problem has multiple solutions. At the core, its a highly rewarding base building and problem solving game with cute critters and animation.

Really good game, maybe with a bit more visual guidance on item purpose or how it works it could be really good.

Been playing on pirated copies for years and finally got the opportunity to support this absolutely fantastic game.
The amount of depth and complexity is astounding and while sometimes incredibly overwhelming makes the experience a hectic, stressful, and rewarding endeavor.
This and both DLC's are both definitely worth it if this sounds like your type of thing.

The graphics are adorable and the game is super addictive! Also, it follows pretty closely to actual science and the learning curve is looooong! I binge this game.

Very fun and a good brain teaser. At times can get frustrating but as long as you take the time to plan your actions out beforehand you should be okay.

its really fun and intresting. it takes time to figure the game out but once you do its fun :).

me encanta flashear que creo energia infinita y que los asteroides que me hacen p1j4 las cosas son en realidad armas nucleares enviadas por asuntos internos

Oxygen Not Included is a fantastic blend of humor and intricate management. It challenges you to build a thriving colony in a harsh, underground world, juggling everything from oxygen production to Duplicant morale. The quirky characters, clever animations, and funny interactions—like panic when they run out of air—add humor to the strategic gameplay, making it both entertaining and deeply rewarding. The game’s complexity, paired with its darkly comedic approach, makes each survival run a uniquely chaotic adventure!

Tactics - Planning - Addictive - Great Game

This game is fun, however it is indescribably difficult to get a good colony. Getting a good colony requires you to find a good seed, and make perfect decisions with no room for error every second of every cycle. This is too difficult to win, not only that, but it is too addicting to lose. You can't leave it alone. You HAVE to try again, THIS TIME it will work.

Extremely fun and challenging, I was highly surprised by how much I actually enjoyed this game.

It's a great game to buy when you need to save up because you won't really be playing other games. Or going out, for that matter

Its like Sims meets physics. If you love factorio, satisfactory or similar, you'll love this too. This is my favourite game out of those as you not only want to scientifically advance your base, but you want to keep all your duplicants happy. That extra bit of purpose coupled with Oxygen not included's endearing animations, awesome mechanics, and its goofyness makes it one of my all time favourite games.

Its definitely not for everyone, but if you like base building and solving progressively harder problems then this game is for you!

Very fun game. It takes a LOT to learn this game. Definitely recommend watching Francis John and maybe even Bier Tier the German Engineer. They teach you how to get the systems connected and your colony functional. A lot of the physics in this game is really interesting. Good use of brainpower while building your ultimate colony!

(Preface: If you're reading this whether to buy the game then probably still go for it, on a "worth it" scale it's in my top 10% of my steam library. There is no consensus on how to use thumbs up/down system so I'm not going to use it for comprehensive review, art and performance or whatnot is out of scope, but rather describe issues that bothered me way too much in a way almost all games in my bottom 50% did not. )

After almost 600 hours in game I'm finally certain this game frustrates me more than it brings joy. It seems like "lot of bang for my buck" but of those 600 getting past ~50 was only possible with mods (though many are being added to the game over time) and everything past 150 was me being victim to sunk cost fallacy, regarding time spent that is, and I finally made the decision to give up on finishing the story.

To clarify frustration: I don't mean dealing with obstacles and unforseen consequences, that's part of the fun. Nor do I mean aspects that are unrealistic but makes sense for simulation to function. It's:
- inconsistencies
- unrealistic behaviours just for the sake of it (that seems to be put in certain places on top of general rules)
- at times good decisions can only be made based on information that is unavailable
Examples (spoilers ahead!) in no particular order, that fall under on or more of these: You can't tell duplicant's what to do, except for when you can, even to go kill themselves. If tasks cannot be realized then reason is given, except for when there is no indication. Why provide melting point (or other info) for some buildings, but not for others. How much fuel does rocket need for a journey? Who's to say, definitely mystery to those who designed them in lore. Switches are controllable by magic from afar but not valves. Making sustainable system of plants and animals is gargantuan challenge, except the intended solution appears to be using magic animal that will let plants grow on say salt with no needs (animal planting plants is great and cute concept, the offense is that the mechanic behind it is not possible to understand using only observation and induction). You can't tell duplicants what to do (again), but you can tell magic doors. Except for you can't really decide which doors since pathfinding seems to have some randomness to it (determining this would require testing I'm not willing to do, but from my observations so far path from A to B is often different than from B to A, also in the pathfinding overlay the paths flicker and change while there is no change to solid tiles or buildings). Duplicants are unaware of checkpoints, from their perspective their function is realized in other dimension, however there is a setting where checkpoints can materialize to their perception but only on a return trip and only when they are full. Oil famously sinks below water. Etc...

And one issue that both makes and doesn't make sense: Since game is about changing temperatures of materials and transition between phases and energy involved... where is latent heat! At one hand it makes sense, most "layers" of the game are basically independent (go figure why DLC introduced radiation), but adding latent heat would increase the complexity of "temperature" layer not 2-fold but 20-fold. However my comprehension of the barrier does not change the fact that it ruins the illusion. All simulators are reductions of reality with many elements missing, but it never bothered me the way this one thing does. There are several heat pumps in game but only as magic boxes. It's like truck simulator without cargo hauling.

Anyhow, especially as an IT analyst I truly admire complexity of this game and effort needed to make it, but regardless, only marvelling at the achievement is fulfilling, actually using the marvel scarcely is.

I love this game, as a scientist I find it extremely satisifying to see how well they implemented all the physics and chemistry inside the game

This game is terribly addictive. I'm constantly finding ways to improve my next round, and I feel like I've only just started. There are a lot of things to learn and so much left to explore, but I am definitely enjoying myself. I would recommend this to anyone who enjoys base-building games. I prefer to use the laid-back version rather than the survival mode, at least at this time, but there are plenty of ways to amp up the challenge for anyone looking for a good survival game.

This is an amazing game. It has lots and lots of common sense, fun and creativity.
I enjoyed it a lot and still love to play it after many years.

Incredibly fun to play. Adorable dupes with their adorable animations. So much content to play with. Eagerly awaiting a sequel or further DLCs! Mods make this even more fun!