Star Wars: A Flicker of Hope
The Eye of the Force
This mysterious and powerful Force artefact has been secretly in the possession of the Baran Do Sages of Dorin for several centuries and is known to bestow superior control of the Sense aspect of the Force.
However, The Eye of the Force causes imbalances in the Force on a planetary level, greatly hindering the use of the Sense Force and Sense Surroundings applications of the Use the Force skill for anyone not attuned to the artefact. The New Jedi Covenant uses this particular property in order to hide their presence on Dorin from other Force-users.