The priority systems of Oxygen Not Included are designed to allow for a high degree of specialization across your base's Dupes. By focusing them into specific roles, you can ensure that a wide range of tasks are always carried out quickly - each will have their own preferred set of tasks and will also gain skill points toward those tasks that boost their effectiveness in their preference.

If you're just here for a quick reference on some good example builds, check the sections after "The Builds" on the sidebar to the right. You're welcome.

If you'd like to know how and why they work, as well as how to make your own, read on. I'd love to help you understand the priority system.

Now, to help de-mystify how ONI manages priorities.




In ONI, the Priority system determines what type of task a Dupe will prefer. As an example, in the image above Turner is set with a "Very High" Research priority, with most of the other task types at their default, middling priority levels or lower. Turner will then always carry out any available Research tasks before considering tasks of any other type. You could literally set the errand priority of a Research Station to 1 and every other task to 9, and he'll will still bee-line it for that Research Station if it's open and he's looking for work to do.

If you look for it, ONI reveals the math it performs to determine task order. A Dupe's personal priority for a task type is multiplied by a factor of 10 and then added to the errand's priority.




Errand priorities allow you to establish the order in which commands are carried out within each task type. As an example, in open areas it's often wise to prioritize construction of floor Tiles and Ladders to ensure accessibility of other tasks. Also, if any Dupe (or build) has matching Priority levels for two different task types, The errand priority can be used to prioritize specific build commands or stations over others of their task type.

As another example, if you set a Dupe to have Very High priority for Operate and Supply tasks (the double up-arrow), setting your Manual Generators to a high sub-priority will ensure they keep the Power flowing before fulfilling random default-urgency supply orders. Once your Batteries are full, they'll then evenly carry out both Operate and Supply tasks until Power needs become urgent again. Once you establish Coal Generators, setting those to also have a high sub-priority will help ensure that they stay supplied with Coal.

Whenever you select a Dupe, the game will display an information window with various details about him or her. To the left of that window will be a visualization of that Dupe's "to-do list."

This picture is taken from quite early in the game before there are many different types of tasks to perform, but it's still informative. Compare Turner's to-do list to his priority settings:



Since Supply has "standard priority" vs the "very low" priority of Build tasks, Turner will try to fulfill every possible Supply task before building anything.

Now for a picture from later in the same game:



Hovering over an item in the to-do list will give you a full, mathematical breakdown of that errand's priority rating. Note that the game does have a default, sub-integer priority it assigns to different task types. However, this is not constant for all tasks of that type, at least in my experience.

The way ONI assigns Dupes to tasks is driven entirely by each Dupe's "to-do list." It does not care where the task is, only how high priority the task is. Even with the "Enable Proximity" option on, the most it will do is try to pick the closest task that closely matches the highest priority, possibly with a very small fudge factor.

Because of this, it's important to consider how these rules work and plan each Dupe's role in a manner that will work well under these constraints. This guide will elaborate on a few "Dupe Builds" that I have found extremely helpful that work well with these rules in mind. While they may be a little tricky to understand at first, they make creating specialized Dupe builds possible, allowing 6 specialist Dupes to do the work of 8 or even 10 generalist Dupes. Thinking about Dupe specialization when picking a Dupe will help ensure you keep a well-balanced workforce for your base!

Note that, in general, you should avoid racing a Dupe through their Skill tree - carefully note how each Skill they learn affects their Morale expectation (the red bar) and feel free to stop progressing to prevent stress buildup across your base until you can manage it well. In the early game and early mid-game, you usually have to consider Morale as you train your workers - make sure your Dupes will always have a higher Morale level (longer green bar) than they need (red bar)! Don't worry - you have a lot of time before most of the high-end jobs become necessary - there's generally more than enough time for job training.

With that, let's get to the builds!

If you're completely new to ONI, you might be wondering what Dupes to take at the start - it's not necessarily very clear. Just in case that's you right now, here's my suggestions.



While you can't directly pick perfect Dupes, you can pick Skill types that will be a guaranteed interest for any Dupes generated in that slot. Use that feature to aim for the following approximate specs:

• Research - for a "Researcher"
  
  • Aim for 1-2 interest versions. High Research is powerful.
    
  • The best 'second interests' are Suit Wearing and Supplying for this type.
    
• Digging - for a "Pioneer"
  
  • Aim for 2-3 interest versions - make sure the Dupe also has the Building interest.
    
  • An ideal third interest would be Operating, but that only matters much later.
    
  • Alternatively, Supplying and Suit Wearing are both very useful for exploring in dangerous areas.
    
• Supply - for a "Foreman" or "Sweeper"
  
  • Aim for 2 interest versions, though any count is probably fine.
    
  • Since we're just starting, we could use either Farming or Cooking interests as a stop-gap until we get a dedicated Dupe for that.
    
  • Suit Wearing would be a better long-term interest selection, if you want to optimize that way instead.
    
  • Alternatively, Operating will facilitate building certain advanced structures later.
    

While there are some traits to favor and some to avoid, I'll leave those details to my early-game guide:

https://steamcommunity.com/sharedfiles/filedetails/?id=1359110726


For an example selection, I picked these three for that guide's playthrough:



Keep in mind that the more your Skill selections align with the Dupe's interests, the easier a time you'll have maintaining their Morale expectations.

The sections after this one are devoted to a description of each Dupe build, why it works, and a useful set of priorities to use for Dupes of that type.

In a standard run, you will likely only need a single researcher, but it's an incredibly important role for developing your base during the early to mid-game. Research is how you unlock new technologies and buildings and is now also involved with geological analyses of the various Geysers you'll discover as your Pioneers branch out through the map. In the late-game, Space opens up with even more research possibilities and the potential to train Astronauts.

This Dupe's natural focus is the Research skill tree; earning the first skill (Advanced Research) is enough to allow a Dupe to operate a Super Computer, which is necessary for any technology after the second tier. As such, they should keep Research as their highest priority. Since they will be the base's research specialist, note that every other Dupe should have a Disabled priority for the Research skill. This prevents the specialist from having their workstation blocked and prevents the other Dupes from getting locked into a task they don't specialize in, as Dupes generally hate changing tasks.

For times when this Dupe is not researching, I'd advise setting a "High" priority for Operate - they'll work other technical machinery and will also prioritize power generation when not busy researching, which can be important for maintaining power to your Research Station if no other Dupes are using your initial Manual Generator(s). Later in the game, this will help them to "tech up" your base with Metals and Plastics.

Quick Learner: a great boost to a Dupe's initial Learning stat, which greatly speeds up research.






Very High: Research
High: Operate
Low / Very Low: Build, Dig - these tend to take researchers far from the core of a base and their beloved Research Stations.

As you enter the mid-game, you should also have this Dupe earn the basic Supply skills. When analyzing Geysers and Vents, you'll generally want to have your researchers in Atmo Suits so that their work isn't interrupted - this will prepare them for Exosuit Training when you can afford it.

As you enter the late-game and start working with rocketry, these two job paths converge as the prerequisites for Astronauts. The game gives you every reason to train Dupes this way, so make the most of it!

Also, note how this Dupe would not have her Morale Need met if she didn't have the interests she does! Interests are quite helpful when they align with your build.

Starting out, you're going to need someone to do a lot of digging, at a minimum. Often you'll need to dig around obstacles, which may involve (at minimum) building ladders to cross gaps or installing doors to safeguard gas pockets. As such, this Dupe is a Digger/Builder hybrid designed for exploring your Dupes' asteroid and laying out the initial paths for others to follow.

At the start of the game, this will likely mean specializing your Dupe at first with Hard Digging. Instead of continuing on as a Miner, however, you should probably give them Improved Carrying I (and possibly II) next so that they can more efficiently supply their building orders. Improved Construction would then follow before continuing with the next Digging skill, speeding up construction as you start more time-consuming buildings. This order has the added benefit of keeping their morale need low while your base's infrastructure is low.

Germ Resistant: a great boost to a Dupe's immune system; these are the Dupes who will spend the most amount of time in germ-infested areas.
Mole Hands: a great boost to a Dupe's initial Digging stat, which greatly speeds up their ability to make new areas accessible.



I generally suggest getting at least Improved Carrying I relatively early into the mid-game, if not Carrying II. Of course, this depends on how much Abyssalite or Obsidian you find in your way.



Very High: Dig, Construction
High: Supply - ensures materials for out-of-base construction if no other Dupes can access their exploration areas.
Low: Operate, Farm, Ranch, Cook - these tasks reflect long activities that should be done within your main base, away from exploration areas.
Disabled: Research, Art - these are specialized in-base tasks that also consume large amounts of a Dupe's time.

If you have in-base builds happening at the same time you want a Pioneer to explore, you can limit access to the exploration area and raise the errand priority of the pioneering tasks to ensure they prioritize exploration over in-base work while the restricted Dupes work inside instead.

A good look at the Skill tree will quickly showcase the usefulness of a hybrid Supplying/Operating build. Conveyor belts can only be built by a Dupe that has cross-trained in both Skill lines, which will take a considerable time investment to facilitate. Fortunately, it's also a very useful early-game build.

With a Researcher focusing at a Station and your Pioneer away exploring, your base needs someone to make sure all the critical needs are met. One very powerful way to do this is to increase a Dupe's carrying capacity - that means fewer and quicker deliveries of important materials to farms, Coal Generators, Algae Deoxidizers and Terrariums, and more. Meanwhile, the Engineering skills help to ensure that all machines are kept operational and efficient; after all, electricity is another important resource for the base. At the start of the game when all you have is Manual Generators, having a Dupe set to High or Very High priority for Operate is therefore very useful. Later on, you'll want this maintained in order to regularly refine Metal or Oil.

Keeping in mind that the end-goal of this Dupe is to unlock resource logistics through constructing conveyor belts and the like, it's useful to devote some time to ranking up this Dupe's Building skills as well. Aim to do this when your base is more or less stable and not in heavy need of Storage or Supply tasks.

Twinkletoes: provides extra Athletics for a Dupe, enhancing their mobility for Supply tasks.
Grease Monkey: provides extra Tinkering for a Dupe, enhancing their proficiency with Operate tasks.





Very High: Supply, Life Support (w/o Sweeper) - Note that Supply includes Construction deliveries.
High: Operate, Tidy (w/o Sweeper) - keep Power high when resources aren't immediately needed.
Low: Dig, Construction - these Dupes should prioritize resource movement over pioneering work.
Disabled: Research, Art - these are specialized tasks that also consume large amounts of a Dupe's time.

As your base grows, Supply errands can rapidly pile up, so having this Dupe devoted full-time to Supply tasks for the early game is quite reasonable.



Very High: Operate, Construction - Operate helps ensure that the base is constantly provided with needed hi-tech supplies and with managing Power room buffs. Construction will be very useful for constructing tech-locked buildings.
High: Supply
Low: Dig- these Dupes should prioritize resource movement over pioneering work.
Disabled: Research, Art - these are specialized tasks that also consume large amounts of a Dupe's time.

More of your Supply-oriented dupes should follow this build than a Sweeper build. While demand for this role will decrease as you increase your base's use of Conveyors, this build is also the one you'll rely on for building Conveyors and Auto-Sweepers long-term later on.

Cooking is a rather time-intensive task with most of its station tasks locked behind the Grilling Skill, so it's wise to devote a Dupe or two to specialize in related tasks. Of course, for a large part of the game, a Quartermaster will often have downtime, so it's wise to give them some useful secondary roles. Farming directly feeds into cooking tasks, while Decoration is also a relatively infrequent task. Since cooking and art are both Morale-oriented tasks, it makes sense, when possible, to combine these two skill lines into a single build - if not adding a third!

We can only select three Dupes to start the game, so while this role didn't make the cut, this is what I'm usually looking to find for my first printed Dupe.

For one variant of the build:



In one game, I had my Quartermaster pick up the Ranching skill so he could function as a backup for the main guy. Another reasonable alternative might forgo the Ranching skill in favor of the Doctoring skills, which is a natural thematic fit for a Quartermaster - supplying the base's medicine.



Very High: Cook. 'nuff said.
High: Farm, Decoration - sometimes your Farmer may be overwhelmed with farm management tasks and not be able to harvest quickly enough. Having the Cook as backup will help keep the food supply chain moving.
Low: Dig, Construction - these tasks tend to be far from the base's center, but we want our Cook to stay near the kitchen unless there's nothing else to do.
Disabled: Research - this is a specialized task that also consumes large amounts of a Dupe's time.

Now, I built this Quartermaster to help with Ranching. A Doctoring variant would place Doctoring in High priority instead, most likely.

You should probably wait until getting at least Aesthetic Design before building artworks, since the final quality (Skill-locked) determines the Morale bonus of those buildings.

As you progress through the early game, you may note that Dupes often take a lot of time running around places. While you've probably got someone fulfilling the "Foreman" role, there are some tasks that are just a bit more time critical that the Foreman might ignore at times.

Some of the same skills that go into the Foreman role are quite useful for cleaning the base. Consider the following image:



Note that each stack of debris is worth -10 points of decor - letting junk pile up around areas your Duplicants stay in is a bad idea for managing the Decor-related part of Morale! (This is occasionally reduced by the material properties of the specific debris stack.) As your Pioneers get to work on making space for the colony, it is beneficial to set up a Dupe to clean the debris from areas you are converting into dedicated rooms that other Dupes might frequent - like your Barracks/bedroom, research room, and the Latrine/Washroom. This is where the hybrid
Supplying/Tidying build comes in - the "Sweeper."

As it turns out, the Improved Carrying Skills also boost Strength - a stat that enhances Tidy tasks as well as a Dupe's carrying capacity. Your colony will often lack sufficient work for a purely-dedicated Tidying dupe, so it makes sense to fulfill a few different task types that align with this synergy. There's also the little fact that for mopping tasks, whatever is mopped (Tidy errand) turns into bottles that must be carried (Supply errand) away.

Twinkletoes: provides extra Athletics for a Dupe, enhancing their mobility for Supply tasks.
Buff: provides extra Strength for a Dupe, enhancing their carrying capacity and ability to perform Tidy tasks.



Ignore the Farming skill, of course.



Very High: Toggle, Tidy, Life Support - these tend to be far more urgent (and infrequent) tasks that need rapid responses.
High: Storage - for handling Sweep commands; only critical (very high) priority tasks should override this role. Yes, Supply handles Sweep tasks, not "Storage."
Low: Operate - keeping it below Storage makes sure that your Sweeper automatically sweeps random debris into any available storage space that isn't marked "Sweep-only."
Very Low: Dig, Construction - these Dupes should prioritize resource movement and general base management over pioneering work.
Disabled: Research, Art - these are specialized tasks that also consume large amounts of a Dupe's time.

You should need very few Dupes of this build for your colony, but it's also a critical role to establish somewhat early on for basic base management. Always be sure that at least one Dupe is extremely responsive to Toggle and Life Support needs.

One of the most critical tasks for a fledgling colony is that of ensuring its food supply. Digging out your base will provide a number of Mealwood Seeds and a few Blossom Seeds, true, but this takes a considerable amount of time and spreads out your initial oxygen supply. Also, Mealwood isn't a viable long-term solution - it requires constant manual fertilization and is actually a rather high-maintenance plant.

As you enter the mid-game, it's highly recommended that you begin Ranching efforts. This not only helps to provide a steady stream of industrial resources, but also provides a source of more food in the form of eggs, meat, or both.

As such, the Rancher's role is important on three fronts:

• They are quicker at managing your initial, likely sizable Mealwood farm.
  
• They have a bonus to multiplying seeds, very important for weaning yourself off of Mealwood for the early-to-mid-game. This will also help in the mid-game when looking to multiply other seed types, as you won't initially have access to excessive Bristle Seeds or Fungi Caps.
  
• They keep your critters happy and productive.

In the early game, it's not important to rush them into the Improved Farming I Skill immediately - the food expectation isn't favorable right at the start, and Improved Carrying I can be useful for transporting all of that Dirt to the Mealwood plants. That said, early on in the mid-game is a good time to start ranching, which will require that the first tier Farming skill already be learned, so don't delay it for too long.





Very High: Ranching
High: Farming
Low: Operate - these tasks tend to lock a Dupe down for long periods.
Very Low: Dig, Construction - these Dupes should stay as far away from Pioneer-type work as possible so that they're ready to work the Farm at any moment.
Disabled: Research, Art - these are specialized in-base tasks that also consume large amounts of a Dupe's time.

Note that Supply appears to affect Delivery of Fertilizer and Dirt, so we do want to keep Supply moderately prioritized. That said, Supply-oriented Dupes should fulfill those tasks first.

If you make adjustments to the priorities, just make sure that Ranching and Farming are above Supply on the priority scale so that Ranchers will rely on other Dupes to transport crops whenever there are numerous specialist tasks yet to be done.

In the early game, a Rancher working alongside a Quartermaster can handle just about all of your Farming needs with little issue; you can safely wait until much later to get a true Farming specialist.

As your base grows and becomes more long-term sustainable, feel free to modify the builds to reflect your colony's new needs. Some tasks only become important later in the game, after you've established numerous critical systems for your colony.

For example, once you have stable power and cooling systems in place, it's often wise to establish Operate-focused Dupes to manage Oil and Metal refineries, as well as any Power rooms you may have established. If your Dupe count becomes high enough to worry about multiple construction sites at once, you may wish to create a Construction-focused Dupe or two to manage base-internal construction while your Pioneers handle remote construction tasks.

The true core purpose of this guide is to help you understand the priority system and help provide you with a few basic builds useful to establish an solid early-game to mid-game. Feel free to experiment; I've presented my reasoning for each of the builds to help you understand how they work so that you can design your own in time. While the Priorities system may be somewhat tricky, it's also incredibly powerful when utilized well - make the most of it!