The Complete Beginner's Completely Incomplete Guide to Oxygen Not Included
Dupes are so ridiculously cute they make puppies seem grotesque in comparison. And, like puppies, leaving dupes unsupervised will at best lead to yellow puddles in your clean water supply and at worst to inexplicable suffocation and death.
I will avoid speculation as to the motivations behind the inherent death-wish of dupes. (We must convince ourselves it is nothing to do with us and move on.) And instead focus on some basic tips to help keep them alive.
There are a number of things that need sorting to keep your dupes alive and happy: oxygen, food, bathrooms, etc. For most of these things you will start with something temporary and then upgrade later.
Players tend to divide the game into the early game, mid game and late game. But exactly where people draw the lines between them varies. I have needed to draw some arbitrary lines here as well. This guide is structured as follows:
The base game compared with the Spaced Out DLC
A very brief overview of some of the main differences.
A little bit about interests and traits
Very early game
1) Outhouses, wash basins and access to water
2) Beds (in temporary locations)
3) Power, part 1: the hamster wheel and battery
4) Oxygen: the Oxygen Diffuser
5) The Research Station (and some research)
7) Compost - dealing with polluted dirt
8) Advanced research - the Super Computer
9) Dining room (Great Hall)
10) Plumbing - toilets and sinks
11) Dealing with polluted water bottles and polluted oxygen
12) Dealing with carbon dioxide
13) Power, part 2: Coal generators
Getting started with automation
14) Automating your coal power generator
15) Automating your carbon skimmer
Ranching: optional but useful
While there are benefits to ranching, you don't need to do it if you don't want to. So it is covered as its own optional bit.
Tip: Going where no dupe has gone before: Exploring the map
Know your biomes and geysers.
TIP: decore Cleaning up your mess - decor and debris
Mid (or maybe late) game stuff
Cooling - using AETN or using aquatuner
There are two things to look at here: interests and traits.
Duplicants - aka dupes - will start with between one and three things they are interested in. The fewer the amount of interests, the more points they have in them.
You can choose an interest for a dupe to have using the dropdown menu next to the reroll button.
You can reroll dupes as often as you want. So if you want a stellar researcher, roll and reroll until you get a dupe whose only interest is research.
There are no hard and fast rules here, so don't worry too much about dupe interests. But you will be doing a lot of researching and digging so a common approach is to have:
one digger (or digger/builder)
For your third dupe pick whatever catches your fancy. Some take a second digger, I often pick a rancher (to have a good one when I need them). Anything is fine.
Green traits are positive traits, red traits are negative traits.
Some positive traits are more usful than others but none are game-changingly good. (There are no positive traits that I reroll endlessly to get.)
The one positive trait I'll mention is Diver's Lungs. It means they use less oxygen. It is particularly useful when you're still learning the game. (But don't worry if none of your dupes have it.)
As far as what negative traits to avoid, this is also largely a matter of personal preference. I avoid:
dupes with Allergies as they spend half the day sneezing if you have certain kinds of flowers or plants in your base.
Anemic dupes, because they are really slow.
Narcoleptics. Their naps aren't a big problem, more that they drop things when they fall asleep. A dupe carrying materials up a long ladder will drop the materials when a narcoleptic nap hits.
Flatulent dupes "produce" natural gas. Natural gas is convenient when you get it in large amounts from a geyser, but inconvenient when you get it in small amounts inside your base.
Mouthbreathers. They use more oxygen.
VERY EARLY GAME
1. Outhouses, wash basins and access to water
On the morning of the second day your dupes will go to the bathroom. Even if there is no bathroom. The main goal for the first day (or "cycle" as days are called in ONI) is to take care of this impending yellow-water doom. To do that, you need to:
build an Outhouse.
The outhouse is found under Plumbing in the bottom left.
After using an outhouse, dupes are covered in germs. They will spread these germs to anything they touch. So the secondary goal for the first day is to give your dupes a way to wash their hands after going to the bathroom. To do this:
build a Wash Basin
It is found under Medicine in the bottom left.
You aren't quite done yet. The outhouse and wash basin need resources to work.
Outhouses need dirt. This you will likely have dug up already. If not, mouseover brown tiles in the starting area until you find dirt and dig some up.
Wash basins need water. To access water you need to dig your way to a body of water and:
build a Pitcher Pump
It is found under Plumbing in the bottom left. Just dig your way to the closest water source, we will worry about more permanent solutions later. For now you just want your wash basins up and running.
Once dupes have filled the outhouse(s) and wash basin(s) you can give yourself a pat on the back - disaster averted.
If you didn't quite manage to avert disaster
You can have dupes mop up accidents with the Mop liquid spills command (bottom right, or press "M").
If "stuff" got into your clean water supply, germs will spread in your clean water. The easiest solution for now is to abandon it and dig your way to a new, germ-free clean water source. (Or reload the game.)
It is entirely possible to decontaminate germy water (in fact, we'll cover it later in this guide), but that is more of a mid-game thing.
For more on germs, see "Tip: germ basics"
Do change it, click on the wash basin or sink and use the Set Direction command
One use for this is to only have dupes wash their hands when leaving a bathroom. (They will get germs from using the bathroom, so washing their hands before that is pointless.)
You can specify that you only want dupes to wash their hands when passing in a particular direction.
On top of wash basins and sinks there is a green arrow that shows its use direction(s).
Tip: wash basin and sink use directions
You can set two types of priorities:
Building priorities affect what order dupes will do tasks like building, digging, supplying resources to outhouses or wash basins, etc.
Duplicant priorities make certain kinds of tasks - digging, building, etc. - more (or less) important for individual dupes. We'll look at duplicant priorities later in the guide.
To make sure your dupes get outhouses built during your first day, you can raise the priorities of the dig & build commands needed for that.
To change priorities, click on Priority in the bottom right (or press "P").
The default priority of tasks is 5. Choose 6 (or higher) for the necessary dig & build tasks to make sure they are taken care of first.
Priorities also affect the everyday maintenance of buildings. After 15 "visits" an outhouse will be out of order until emptied and restocked. To avoid future "accidents," you will want your outhouses to be emptied as soon as needed. Also, to avoid the spread of germs you will want your wash basins to always have water.
It is highly recommended to raise the priority of your wash basins and outhouses. (I use 8 for outhouses and 7 for wash basins. But just make sure they are above your default values.)
A note on priority creep. Speaking of default priority values, you might be tempted to keep raising more and more priorities to "get things done quicker." We've all tried this. It hasn't worked for any of us. Once everything is priority 9, nothing is priority 9.
Tip: getting the right things done first using Building Priorities
If a dupe is germy when they pass a wash basin or sink they will automatically wash their hands. But:
Only one dupe can wash their hands at a time. If there is no free wash basin, dupes will not wait their turn. They happily run on and start spreading germs. To avoid this, build one wash basin for every outhouse.
Dupes will not intentionally look for a wash basin or sink after using an outhouse. You need to design your base so that they automatically pass one. A common way to do this is through door permissions.
Controlling dupe movement using door permissions
When you have built a door (found under Base in the bottom left or by pressing "1") you can change its settings. One thing you can do is set a door so that it can only be passed in one direction.
If you build your outhouses on one side of the room and wash basins on the other, you can have the door on the side of the outhoses to only let dupes in, not out. That way dupes will pass a wash basin regardless of which direction they entered the room from.
Tip: making sure dupes wash their hands
A germy dupe spreads germs to things they touch - ladders, machines, beds etc.
To see germs in your base, click on the Germ Overlay in the top right. (Or press F9.)
If a dupe is germy, click on the dupe and then use the "Move to" command to make them run past a wash basin to wash their hands.
If germs manage to spread in your base you can have dupes disinfect things using the Disinfect Buildings button on the bottom right. (Or press "I".)
If germs are a constant problem, check to make sure: 1) you have a wash basin for every outhouse, and 2) dupes must pass a wash basin after using an outhouse. (It could also be a food related problem - we'll cover that later.)
Tip: germ basics
2. Beds (in temporary locations)
Dupes will get a debuff from sleeping on the ground.
(It isn't really a big deal and, to my shame, I often let them sleep on the ground for a cycle or two before getting around to beds. I mainly included beds this early in the guide to give the impression of being less heartless than I actually am.)
To avoid the debuff:
build each dupe a bed - called a Cot, found under Furniture in the bottom left.
You can build the beds in temporary locations, the goal is just just to avoid the debuff. However, there are a few things to keep in mind when deciding where to put beds, even temporarily.
By default, dupes will not sleep well if:
it is too bright. For instance next to the printing pod, or if there is a shine bug nearby. (You can access the Light Overlay on the top right or by pressing F5.)
They are sleeping next to a snoring dupe
If you have a snorer (called a "loud sleeper"), leave two spaces - the width of a cot - between their bed and other beds.
You can assign beds to specific dupes, useful for instance to make sure a loud sleeper sleeps in the right bed.
3. Power, part 1: the hamster wheel and battery
Your first source of power will be the Manual Generator, commonly known as the hamster wheel.
The hamster wheel generates power while a dupe pedals on it. As soon as the dupe stops pedaling, the hamster wheel stops generating power - and any machines hooked up to it stop working.
For machines to continue working after a dupe stops pedaling, you need to connect a battery to store power.
Build a Manual Generator (under Power, bottom left)
Build a Battery (also under Power in the bottom left)
The battery needs to be connected to the hamster wheel.
Use Wire (also found under Power) to connect the socket on the hamster wheel to the socket on the battery.
Laying wire will dig up earth tiles but will not destroy duplicant-built tiles. So if you want to keep your base tidy by hiding your wiring (and what kind of monstery wouldn't want that?), build floor tiles for the wiring to go along.
On where to put things. You will develop a personal preference for where to put hamster wheels, batteries, etc. Until then, don't worry about placement. Stick them wherever - they are easy to move later if you change your mind. (We will be upgrading to coal power soonish anyway.)
4. Oxygen - enter the Oxygen Diffuser
The starting biome comes with some oxylite - tiles that emit oxygen as they slowly dissolve. They will keep you in oxygen for your first few cycles. With bathrooms and power sorted, it's time to sort out oxygen.
How to produce oxygen will depend on what asteroid you chose - what type of "biome" you are in. I will assume you are in a beginner-friendly biome. Meaning, one that has Algae. (Mouseover green tiles to find algae.)
Build an Oxygen Diffuser (under Oxygen, bottom left)
Using Wire (under Power), connect the oxygen diffuser to your power grid.
The oxygen diffuser turns algae into oxygen. Dupes will fill it up automatically, you don't need to do anything about it. (However, I usually change the oxygen diffuser's priority to 6 to make sure it gets done.)
The placement of the oxygen diffuser isn't hugely important, but putting it near a ladder system going through your base will make it easier for oxygen to flow.
You can save some travel time by storing algae near the oxygen diffuser. To do this,
Build a Storage Bin (under Base, bottom left) near the oxygen diffuser
By default, storage bins don't accept any materials. To change this, click on the storage bin. You can set it to accept all materials or any combination you want.
Change the storage bin to only accept Algae, found under Organic.
There are a number of different gasses in Oxygen Not Included.
The main ones you will come across in the early game are oxygen and carbon dioxide. And possibly some chlorine and hydrogen.
To see oxygen levels - and other gasses - in your base, click on the Oxygen Overlay in the top right. (Or press F1.)
Over time, gasses will settle in their own layers: hydorgen rises to the top, oxygen below it, then chlorine and at the bottom your carbon dioxide.
You can improve gas flow in various ways. An easy one is by having a somewhat spacious ladder shaft (or several). Instead of building a ladder with rooms immediately on both sides, leave an empty space on either side of the ladder. (Dupes can jump over one tile.) The extra space will improve airflow and also be useful for fire poles (Weeee!) and gas vents later in the game.
Tip: oxygen and gas flow
5. Get your research on with the Research Station
Lots of useful stuff needs to be researched before it unlocks. So now:
Build a Research Station (found under Stations, bottom left)
Connect it to your power grid
The research station requires dirt. So it isn't a bad idea to:
Build a Storage Bin (under Base) near the research station and set it to store Dirt (found under Cultivable Soil).
Tip: Duplicant Priorities
Now that your basics are sorted this is a good time to set some priorities for your dupes. You can open the Duplicant Priorities menu by clicking on Priorities in the top right.
Here you can tinker with individual dupes' priorities for groups of tasks. You can raise priorities, lower priorities, or entirely forbid dupes from doing certain kinds of tasks. (Using the left & right mouse buttons.)
How to set your priorities will depend on what dupes you chose. Change priorities accordingly - research for researchers, building and digging for builders and/or diggers, etc.
Note: Later, you can expand your base to have enought dupes to have them focus on only one kind of task. But for now you will need to make sure one of your three starting dupes also takes care of the hamster wheel - so the base stays powered. And that someone empties and cleans the outhouses when they are full - so you don't have accidents.
The hamster wheel priority group is "Operating"
Wash basin and outhouse maintenance is "Tidying"
You can either raise those priority groups for some dupe or have a "general purpose" dupe without individual priorities, who will instead decide what to do based on Building Priorities.
Whatever your decide, it is a good idea to raise the Building Priorities for the hamster wheel (I usually have it on 6), the wash basin (I usually go with 7) and the outhouse (I have it at 8).
Duplicant priorities versus Buildig Priorities
When dupes choose what to do, Duplicant Priorities come before Building Priorities. If you have a dupe with a raised Duplicant Priority in digging, they will prioritize digging over other tasks - even if the other tasks have a higher Building Priority.
By way of example, if you have a row full of outhouses that need emptying, and they are all set to priority 9 because things are about to go sideways, then the dupe with a raised digging priority will keep digging - regardless of the Building Priority of the dig commands. A priority 1 dig command will win over a priority 9 command for anything else if the duplicant has a raised priority for digging.
To get your basic foor sorted you will need to do some research.
Research Basic Farming, found in the Food category of research.
It won't take long. When done, you can build the Planter Box (under Food, bottom left).
Build (at least) 5 planter boxes for every dupe you have.
Plant Mealwood Seeds in them.
Note: After setting one Mealwood seed to be planted you can select the planter box and use the "Copy settings" command to issue plant commands in other planter boxes. (So you don't need to plant them all individually.)
You might not have enough Mealwood seeds to fill all planter boxes. Don't worry - you will unearth more seeds as you expand your base.
7. Compost - dealing with polluted dirt
Your outhoses will produce polluted dirt. Researching Basic farming also unlocks the Compost (found under Refinement in the bottom left). Dupes can use it to turn polluted dirt into dirt.
(I should perhaps mention that some players just ignore outhouse polluted dirt. I use composts.)
Note: polluted dirt can have germs. Transporting germy things give dupes germs. So it is a good idea to have the compost behind a wash basin. (I usually put my compost with my outhouses.)
To keep improving your colony you will need to do more researching. So let's cover some research basics.
There are four different kinds of research:
Materials Science Research
Each kind of research requires its own research station.
Each research station requires its own materials to conduct resarch.
Novice Research is conducted on the Reseach Station (found under Stations), using dirt.
Other research stations need to be unlocked through research.
Anyone can do Novice Research. Other kinds of research require skill points devoted to them.
Tip: research basics
The second type of research is conducted on the Super Computer, using water.
The Super Computer is unlocked through researching Advanced Research in the Colony Development research branch.
Advanced Research (the kind done on the Super Computer) requires the Advanced Researching skill, which is unlocked by spending one skill point in Researching.
All early game builds - and lots of mid-game builds - can be completed through unlocks using only the first two kinds of research.
(So don't worry about the other kinds of research yet - for now you just need dirt and water. Easy-peasy.)
8. Advanced Research - the Super Computer
The second kind of research (Advanced Research) requires two things: a Super Computer and a dupe with one skill point spent in Researching.
You unlock the Super Computer through researching Advanced Research in the Colony Development branch of the research tree. (You will need to research Employment first - you can't skip over research. But that's OK, we'll need that, too.)
When the research is finished,
build a Super Computer (under Stations).
By now your dupes have probably started getting their first skill points. Whatever dupe you have chosen to be your reseracher, spend their skill point in the Research branch of the skill tree to unlock the Advanced Research skill. Then they can use the Super Computer.
It is a good idea to keep your researcher busy. Keep researching stuff, anything that seems interesting - you will eventually want to research most (or all) of it anyway.
Rooms get room bonuses by fulfilling certain requirements.
You can see the available room bonuses and requirements in the Room Overlay (top right, or press F11).
The most common maximum room size is 64 tiles. This equals a 4x16 room: 4 tiles high, 16 tiles wide. (Or 18 tiles wide if you include the outer walls.)
The maximum size for a ranch is 96 tiles. This equals a 6x16 room. (6 tiles high, 16 tiles wide - or 18 if you count the outer walls.)
For my fellow neat-freaks
If you want a neatly structured base you can make your floors 18 tiles wide and then vary room hight depending on the max room size.
(The above suggestion is in no way a necessity, but be warned: years ago I read someone suggest it on a forum, and since trying it for the first time I have been both physically and pshychologically incapable of ever not building my bases using the X tiles high by 18 tiles wide approach.)
Tip: room sizes - and room bonuses
9. A DINING ROOM (GREAT HALL)
Under Furniture (bottom left) you will find the Mess Table. Dupes won't share tables, so you will need one per dupe. If the mess table is in a dining room, dupes will get a morale bonus. There are two different kinds of dining rooms:
Mess Hall (+3 morale)
Great hall (+6 morale)
A great hall is an easy way to get a good morale bonus. (So please build one.) The standard early game Great Hall includes:
A Water Cooler (under Furniture)
Mess Tables for each dupe
A plant (as the necessary decor item)
The Water Cooler is unlocked in Employment, the first bit of reseach in Colony Development (if you have a Super Computer then it is already researched).
The Mess Table is unlocked in Meal Preparation, the second step of the Food research branch.
A plant will require something to plant it in - a Flower Pot, Wall Pot, or Hanging Pot. They are unlocked in the Decor research branch.
You can see the Plumbing Overlay by clicking on the water drop icon in the top right or by pressing F6.
You build most plumbing-related stuff through the Plumbing build icon (bottom left). A notable exception is sinks, which are found under Medicine.
Plumbing things commonly have an input and an output.
White is input: liquid goes in here
Green is output: liquid comes out here
If something isn't working, the first thing to check are the inputs and outputs. A common mistake (even after hundreds of played hours) is connecting inputs and/or outputs wrong.
A pipe must lead somewhere for liquid to flow along it. (A Liquid Bridge counts as somewhere - water will flow up to the start of the liquid bridge, even if the pipe goes nowhere after it.)
If you want liquid to pour out of a pipe, you need to put a Liquid Vent at the end.
Tip: plumbing basics
10. PLUMBING - TOILETS AND SINKS
There are a bunch of useful things that require plumbing. Let's start with upgrading your outhouses and wash basins to toilets and sinks.
Emptying outhouses and wash basins takes time - and produces germy water and polluted dirt. Toilets and sinks require no maintenance. So it's a useful first plumbing project.
For this build, you will need to research:
They are all in the Liquids research branch.
Building this project includes the following steps (the order you do them in doesn't matter):
Build toilets - called Lavatories, found under Plumbing - and Sinks, found under Medicine.
(When deciding where to put toilets and sinks, remember the stuff about germs and making dupes pass a sink to wash their hands after using the bathroom.)
Build a Liquid Pump (found under Plumbing) in a body of (clean) water.
Build a Liquid Reservoir (found under Home). Placement isn't hugely important, but try to put it somewhere where it won't be in the way for several dozen cycles (or more).
Using Liquid Pipe (under Plumbing), connect the water pump to the toilet and sink inputs - the white bits.
Also using pipes, connect the toilet and sink outputs (the green bits) to the input (the white bits) of the Liquid Reservoir.
The finished piping should go:
from the pump to the white bits on the toilets and sinks.
from the green bits on the toilets and sinks to the while bit on the liquid reservoir.
When finished, connect your Liquid Pump to your power grid (using Wire, under Power).
Water should now start flowing along your pipe(s) and into your toilets and sinks.
Mouseover your toilet and, if everything worked, it should say "Lavatory Ready." If it doesn't say that (and trust me - we've all been there), it's time to start debugging - start by checking inputs and outputs.
11. DEALING WITH POLLUTED WATER BOTTLES AND POLLUTED OXYGEN
You will end up with polluted water bottles in your base, from your early toilet setup and from any accidents your dupes may have had. With some plumbing basics researched, we can now get rid of them.
To do this, we will set up a place to dump the polluted water, with a pump to pump it into the liquid reservoir of polluted water. This can either be a temporary thing you deconstruct afterwards or a permanent place for dupes to dump polluted water bottles in the future.
Dupes get germy from carrying polluted water bottles. Once this project is done, send germy dupes past sinks to wash their hands and do a large-scale disinfection of the base - using the Disinfect buildings command on the bottom right (or press "I").
12. DEALING WITH CARBON DIOXIDE
Dupes exhale carbon dioxide (you can see the Oxygen Overlay by clicking its icon in the top right or pressing F1).
When carbon dioxide levels rise into your base, dupes will have to intermittenly run up into the oxygen layer to gasp for air. So having a machine (or worse - a bed) in carbon dioxide isn't great.
There are two approaches to carbon dioxide buildup in your base: Deal with it later and Deal with it now.
Deal with it later
Since carbon dioxide is heavier than oxygen, you can dig a carbon dioxide pit: basically just a ladder going down, with a few tiles dug out around it. Then you can extent the ladder further and further down as carbon dioxide piles up in your base.
Note: digging a deeper and deeper carbon dioxide pit will become slower and slower as dupes need to hold their breath for longer and longer as they go down to dig.
Deal with it now
Later in the game there is some limited use for carbon dioxide. For now, let's just get rid of it. We'll do this with a Carbon Skimmer.
Carbon skimmer basics
The Carbon Skimmer is unlocked through research: under Air Systems, the second step in the Liquids research branch.
The carbon skimmer uses water as its input and outputs polluted water.
(Though polluted, the water is germ-free.)
The carbon skimmer only gets rid of carbon dioxide - it does not produce oxygen.
Carbon skimmer placement
The carbon skimmer will define the point where oxygen will end and carbon dioxide will begin: carbon dioxide will build up to the carbon skimmer, not above it.
When deciding where to place your carbon skimmer
one option is to put it at the botttom of your base. (Or to dig down to what you think will be the bottom of your base once you are done expanding.)
Another option is to put it further down your ladder network. You will eventually want to dig down to the oil biome (but don't go there without Atmo Suits! - we'll cover them later) and other biomes below your starting biome. A carbon skimmer further down a ladder network will mean dupes can breathe there, too.
It might not seem like it when you first start playing, but heat has ended many a game of Oxygen Not Included.
The way heat usually gets you is your food: Mealwood and Brislte Blossoms can be at most +30 C to grow.
With late game technology you can keep your base cool. Until then, you need to give some thought to it.
Buildings generate varying amounts of heat. You can see the amount they generate in the build menu under Heat.
The amount of heat generated is given in DTU/s. I have absolutely no idea what that is. But comparing buildings will give you some idea, e.g.:
a Ceiling Light generates 500 DTU/s
a Rock Crusher generates 16.000 DTU/s
Try to keep buildings that generate significant amounts of heat a fair distance away from any area where you grow food.
Tip: heat basics - food
13. POWER, PART 2: THE COAL GENERATOR
The hamster wheel is adorable, but can take a significant amount of time out of your dupes' day. Also, you will eventually need more power than a hamster wheel can provide.
You can free up dupes for other taks and have more power available in your power grid by upgrading to coal power. (If this seems intimidating, don't worry - you will have it up and running in no time.)
8) Great Hall
9) Refined metal
10) Dealing with carbon dioxide
11) Plumbing - toilets and sinks
12) Power, part 2: Coal generators
13) Cleaning up your mess - decore and debris
oxygen cealning and polluted water form toilets
Optional (but useful): Ranching
While there are benefits to ranching, you don't need to do it if you don't want to. So it is covered as its own optional bit.
Getting stared with automation
Automation is a huge help and you're better off getting over any fears of using it right away. Which is what this next section will do.
14) Automating your coal power generator
15) Automating your carbon skimmer
Mid-game stuff, part 1
Rooms and bonuses
Decor, cleaning up
Know your biomes
Know your geysers etc.
Toilets and wash basins
Access to water
Beds (in temporary locations)
Power (hamster wheel) and battery
Advanced research station