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A book which explores dark psychic powers, the void hidden under space, and the dreams of evil superintelligences. These volumes can help a reader harness dark entities and powers.

Base Stats

Exotic itemBook
Market Value
250 Silver
Stack Limit
0.5 kg
Deterioration Rate

Tomes are a type of book that provides recreation while generating research points for Anomaly research.


Tomes, like standard books, can be purchased from trade caravans, orbital traders and faction bases. However, tomes are more exclusive than other books, and are generally only carried by exotic goods traders.


Tomes can be read by colonists as a recreation activity, with a recreation power of 1. All books will also train intellectual at a rate of 250 XP per in-game hour.

Tomes function identically to schematics, with two major exceptions: They only progress dark research projects, and they have a chance to cause mental breaks while being read. Higher quality tomes provide more research points when read. The chance for the tome to cause a mental break per hour while read is randomly selected when the tome is generated, from a range of 1% to 5%

Tomes have a 25% chance of generating with two research projects instead of one. Reading the book will progress both projects at once, but the number of points generated will be divided by 1.6. Completing one of the two projects will not negate this effect, making the tome less effective overall.

Effects of Quality on Research
Quality Points
1 project 2 projects
Awful 0.07 / Hour 0.05 / Hour
Poor 0.15 / Hour 0.09 / Hour
Normal 0.23 / Hour 0.14 / Hour
Good 0.30 / Hour 0.19 / Hour
Excellent 0.38 / Hour 0.23 / Hour
Masterwork 0.45 / Hour 0.28 / Hour
Legendary 0.52 / Hour 0.33 / Hour


The main use of tomes is to progress anomalous research without the need to capture or contain dangerous entities. Entity study requires the construction of large containment facilities, and comes with the risk that the entities may escape. Tomes require no infrastructure to use, and the only threat they pose are the mental breaks they cause, which can each be dealt with in their own ways.

The main drawback to tomes is that each one can only be used to progress its associated research projects, while entity study can progress any research project within the entity's knowledge category. Another advantage of entity study over tomes is that studied entities can additionally be exploited by bioferrite harvesters and electroharvesters for bioferrite and power respectively (though the latter does halve the amount of research gained from entity study).

There is a practical use for the tome's ability to cause mental breaks, even after all anomalous research has been completed, as it can inspire colonists with the tortured artist trait. As long as the mental breaks can be dealt with, the resulting inspired creativity can allow for the creation of many high-quality items within a relatively short span of time. To minimize the interval between breaks/inspirations with less micromanagement, tortured artists can be assigned to an allowed area that contains no form of recreation other than tome-reading.

If you do not intend to give pawns mental breaks, however, then reading tomes over other books is actively detrimental. You can adjust your colonists' reading assignments to exclude tomes from the list of allowed books, while still keeping your tomes in bookcases to contribute to a room's reading bonus.




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