Ysalamiri

Ysalamiri (singular ysalamir) are furry, lizard-like creatures from the Star Wars continuum, first appearing in the Thrawn Trilogy. They are highly sought after for their ability to negate the powers of any Force-users in the vicinity.

In Canon
Ysalamiri live on the planet Myrkr, where they feed on the sap of trees. This left them easy prey for vornskrs, predators that hunt using the Force. Eventually, the ysalamiri evolved the ability to create a bubble in which living organisms are unable to manipulate the Force.

Grand Admiral Thrawn discovered a way to keep ysalamiri alive while off their trees, and kept them on his person to shield himself from the attacks of Force-users.

In the PPC
Ysalamiri played a minor role during the Reorganisation. After the Sunflower Official had learned the Mysterious Somebody's identity, Nyx Nightingale captured wild ysalamiri to keep Dassie Hyrax free of the dark Jedi's mind control.

Appearances
Ysalamiri are used in chapters 11 and 12 of the Reorganisation.
 * "Revelation" and "Judgement"