Force stealth

Highly skilled Force users can use Force Concealment to mask their Force alignment (Light or Dark), their ability to use the Force, or even their enitre presence from others who are Force sensitive.

This ability manifests in different forms; Vergere would shrink her presence in the Force to a microscopic size, where she was almost undetectable, whereas Asajj Ventress was taught the Quy'Tek mediations to shield her presence. The most notorious user of this talent was Darth Sidious who concealed his true nature for decades from even the Jedi Council.