There are a total of 308 (we think!) different species of companions, all active. (This number is from early February 2019).
Click on the name of each species type to see more details about the species, its source(s), and detailed bonus information.
Companion attributes (stats)
Your companion can give you and your trap set-up a number of attributes when you acquire it. Some stats increase as your companion levels up; other's don't. Some stats can be increased through an augmentation. See the linked pages for more details.
Compare companion stats
You can compare the stats of all of the companions using Companions compared. Note that stats that change in value as the companion levels up are shown as "beginning value – ending value". Those stats change an equal amount at each level.
Once your companion has reached level 5, you can augment its attributes .... for a price.
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