The Phobis devices represented Sith artifacts designed to exploit fear, affecting individuals through simple contact. These devices, saturated with dark energy, induced debilitating terror in almost all who encountered them. A trio of these machines existed, with the central component of one being secured within the Dark Temple by the Sith Emperor; it likely emanated fear and triggered widespread panic for countless years. Numerous Sith attempted to unlock the mysteries of these machines through meditation, but this resulted in their descent into insanity. Only the Dread Masters managed to comprehend and control their capabilities. They effectively mastered the sinister power of the Phobis devices, deploying it as a weapon against the Republic.