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Oxygen Not Included Wiki
This article has not been revised for the current version (U40-494396). It was last updated for LU-356355. It may contain inaccuracies.
This article has not been revised for the current version (U40-494396). It was last updated for LU-356355. It may contain inaccuracies.

Hatch is a Critter found in the starting Temperate Biome. They produce Coal, Eggs, Meat, and Refined Metal. They can be domesticated.


This creature is nocturnal and eats minerals in its path. It burrows into natural tiles with a hardness of 20 or lower to hide for the day time, and the tile in which it's burrowed can be dug up to encounter the creature. These DO include natural tiles with "buried object" in them and are surround on all sides by other natural tiles. If there few starting surface hatches, simply excavate some of the starting biome to quickly encounter more.

It drops 3200 kcal (2 kg) of Meat on death.

Hatches convert a certain percentage of the eaten mass into another resource (e.g. regular hatches eat 140 kg of solids and convert them into 70 kg of coal).

Note that regular hatches and sage hatches can also eat food. However, they only eat a few grams of food and thus only convert it into a few grams of coal. Because of this, food is not a good diet if you want your hatches to provide the coal for a Coal Generator.


The Hatch has four variants, each with its own varied diet preferences. Along with the plain hatch, two of its variations provide a greatly diversified diet that may be better tailored to the needs of your colony's coal production. The final variant provides a refining service that is otherwise heat intensive, power hungry and time consuming.

For details on how to get the different variants, see Critter Morphs.


Hatchling Egg.pngHatchling.pngHatch.png

The Hatch that is the purple, toothy critter your Duplicants seem to stumble upon in their initial excavations. It eats a wide variety of the same foodstuffs your duplicants subsist on, along with some minerals, and produces coal in return. It provides a minor decor bonus (+10) in its immediate radius. If fed Sedimentary Rock, it has an increased chance of producing a Stone Hatchling Egg. If fed Dirt, it has an increased chance of producing a Sage Hatchling Egg. When killed it provides 2000 g of meat.

Sage Hatch[]

Sage Hatchling Egg.pngSage Hatchling.pngSage Hatch.png

Sage Hatch have a glossy green color, and a green diet to match. It consumes almost exclusively organic compounds, including Polluted Dirt, slime, and algae, alongside every normal foodstuff your dupes eat such as Meal Lice. It produces coal in return. It is completely indifferent to bacteria or spoilage, and effectively consumes otherwise spoiled, inedible or over abundant organics your dupes can't use.

Sage Hatch has the highest conversion rate among all four variants. It can convert 100% consumed mass into Coal.

As you will likely have many more minerals than organics, it is usually more efficient to use normal or stone Hatches for coal production, and to use Pokeshells or Compost for Polluted Dirt or expired food disposal. Algae is better used for oxygen production or Pacu farming, while slime can be stored underwater to prevent offgassing and used to farm Dusk Caps. However, when attempting the Carnivore or Locovore Achievements, Sage Hatches can be a way to make use of otherwise useless Dirt and Fertilizer.

Stone Hatch[]

Stone Hatchling Egg.pngStone Hatchling.pngStone Hatch.png

Stone Hatch are flinty grey and have a thickened, rocky appearance. They consume primarily mineral materials such as Igneous Rock. They also consume some Raw Metals, such as Copper Ore or Iron Ore, producing an equal volume of coal in exchange.

If fed Copper Ore, Gold Amalgam, Iron Ore, or Wolframite the Stone Hatch has an increased chance of producing a Smooth Hatch egg.

This variation is considerably tougher than normal hatch, with more hp and attack, and caution should be used when attempting to kill it as it could severely injure or kill a lone dupe.

  • It is wise to consider wrangling them before killing them. No critter can break out of wrangling, not even these, and wrangled critters will not break free if they are shot at either.

Smooth Hatch[]

Smooth Hatchling Egg.pngSmooth Hatchling.pngSmooth Hatch.png

Smooth Hatch are a deep cobalt blue. They eat metal ore exclusively, and instead of producing coal, they produce Refined Metal of the corresponding ore instead. They will eat a 100 kg of ore, "refining" it into 75 kg of Refined Metal. They retain the "tougher" stats of the Stone Hatch and thus are dangerous to fight alone should you order your dupes to attack one.


Hatch Farming for Meat and Eggs[]

A Duplicant requires 1000kcal per cycle on normal difficulty settings (default). A hatch provides 2,000 grams of meat when slaughtered, which translates to about 3,200 kcals of food, 4,000 when cooked into barbecue.

Happy Hatches take 5.88 cycles to lay an egg. This is roughly 544 kcals in meat (or 680kcal in barbecue) per cycle, meaning in theory you need 1.838 (or 1.47) hatches per dupe. Happy Hatches can lay up to 16 eggs over their entire adult life (95 days), one of which will be needed to repopulate the stable; therefore, over a hatch's entire 100 cycles of occupying a stable, it will provide 15 eggs for the colony. This is 480kcal in meat (or 600kcal barbecue) per cycle, meaning you need 2.08 (or 1.67) hatches per dupe.

One egg can be cracked into 1,000 grams of raw egg, which can be turned into 2,800 kcals of omelette. Since the same calculation holds true as above, this is 420 kcals a day, meaning you need 2.38 hatches per dupe. This feeds about half a dupe less per stable (or one and a half dupes less when cooked to barbecue), requires therefore more space, but can be done with little or no automation and therefore can be done easily early game.

The eggs need to be moved to another room to incubate so they don't prevent new eggs from being laid and if you don't use an incubator there will be a long delay before your first harvest.

Hatch Coal Herding[]

The goal of setting up this kind of herding operation is to have (Stone) Hatches producing coal at a rapid rate. Each Coal Generator consumes 600 kg of Coal a Cycle when running constantly. You need 8.5 tame and happy (Stone) Hatches to produce 600 kg of coal each cycle. You can fit at most 8 hatches in one Stable, so technically you would need more than one stable to fuel one coal generator constantly. However, usually coal generators don't need to run all the time so your actual requirements may be less.

If there is a Volcano on the map and its Magma is cooled down into Igneous Rock, feeding it to Stone Hatches provides a renewable way to produce coal.

Hatch Garbage Disposal Herding[]

Sage Hatch will eat spoiled, over abundant or bacteria laced food, converting undesired mealwood, spoiled food, polluted dirt or slime into Sage Hatchling eggs and meat alongside a limited supply of coal. They make for delicious barbeque and a consistent stream of eggs (one every 6 cycles roughly). Your Ranch room should have a separate hatchery adjoining it to provide constant hatch rearing. Typically a herd of 7 will run one generator, which can provide the power to a couple incubators.

Hatch Refinery Herding[]

Smooth hatch refine metals, more efficiently than a Rock Crusher, but less so than a Metal Refinery. While it takes some investment to breed a Smooth hatch, once obtained they can provide a reliable source of refined metal, without needing power and a dupes time, apart from grooming if needed, and without generating large amounts of heat. Careful estimation of just how much refined metal you need should be made, and the number of hatch should be carefully managed unless you wish to find yourself running out of ore. 3 - 4 Smooth hatch can produce enough refined metal for most early - mid game needs. They continue producing eggs like other hatch sub-species, though caution must be exercised when harvesting full grown Smooth hatch for meat - they can incapacitate a lone unskilled dupe easily. As such, if smooth hatches are also ranched for meat, use of a Drowning chamber is recommended.