Resurrector mech serum

The resurrector mech serum is an item found in quests that can resurrect any deceased human or animal.

Acquisition

Resurrector mech serums cannot be crafted nor bought from traders. Instead, they can only be acquired as a reward for performing quests or found in ancient shrines. Note that quest rewards are selected with a weighted random generator, so there is no way to guarantee access to a serum in a given play-through.

Anecdotally, it is often reported that the increased number of reward options added by the DLC dilute the reward pool with more options.

Summary

A resurrector mech serum can be used on any non-desiccated corpse, even rotting ones. Select a colonist and right-click the serum, then click a valid target. They will use the serum on the corpse, returning it to life. This will restore missing organs and eliminate all health problems, except for brain injury and Luciferium addiction. Artificial body parts are not affected.

Using the serum removes the "Tainted" tag from any clothing worn on the dead. Any eligible title is immediately passed on to the heir, and won't be recieved even when revived.

Resurrection ailments

Once revived, pawns will initially be incapacitated due to resurrection sickness. Besides this, they may suffer from permanent side effects. The chances are reduced when used on a corpse that has had less time to rot, by quickly reviving/freezing them. Possible side effects are:

Dementia
Blindness
Resurrection psychosis, visible 10 days after usage

For all of the above, the initial chance is 2%, linearly increasing to 80% after 5 days of decay. Each are applied separately.

Analysis

By destroying the head, the resurrector mech serum can be used to heal brain injuries. Extracting the skull will destroy the head safely and consistently. Without the Ideology DLC, you can eat the corpse. However, this is inconsistent and risks them consuming the corpse entirely. By intentionally killing a pawn, this can be used as a substitude for a healer mech serum, but always comes with the risk of resurrection psychosis, which is inevitably fatal unless a healer mech serum is used.

Using it on an enemy corpse will not convert them towards your side. They will remain hostile. However, since they return to life incapacitated, you can easily arrest and capture them.

Corpse preservation

Colony pets may feed from the corpse of the intended body if within reach.
Storing dead colonists in a freezer or other cold room will allow for resurrecting them long after death without higher risks of side effects. It may be worth constructing a room with sarcophagi in it if you wish to preserve them.