Heartrenders are Grisha of the Corporalki order. They can use their power to damage a person's internal organs. Their ability ranges from slowing a person's pulse to snatching the air from their lungs. The target must be in their line of sight. They are feared by other Grisha and considered the most valuable soldiers. In the Second Army they wear red kefta with black embroidery.
Heartrenders manipulate the body on a molecular level, usually with harmful affects.
- Lungs: They can take the air out of a person's lungs and keep them breathing as long as they're in the Heartrender's influence.
- Heart: They are able to induce heart attacks, slow breathing to the point of loss of consciousness, or quicken the heartbeat to dangerous speeds.
- Hampering Healing: They can slow the healing process, rather than quicken it.
- Influencing Emotions: By encouraging the release of certain chemicals in the body, Heartrenders can influence a person's emotions.
When on parem, a Heartender's abilities are heightened to an extreme level. Nina Zenik, a talented Heartrender, claimed that just one of them on parem would be able to tip the scales of a war between nations.
- Mind Control: When under the effects of parem, they're able to force a large group of people to follow their commands.
- Tailoring: If the specific Heartrender has any talent with Tailoring, it would be amplified to a master level.
- Enhanced Sight: By increasing the range of their sight, jurda parem allows Heartrenders to affect targets at much farther ranges than usual.
- Like all Grisha, they can't use their abilities when the movement of their hands is restricted.
- They require sight for their powers to affect their targets. Anyone too far away, obscured from complete sight or out of their range of vision couldn't be influenced.
- Heartrenders' abilities seem not to have any effect on animals.
- After recovering from the effects of parem, Nina's abilities change markedly; she seems to have lost the ordinary abilities of a Heartrender, and gained an affinity for manipulating dead and decaying flesh and bone.