An artifact of unknown origin the size and shape of an ostrich egg, but smooth and black like obsidian. People with telepathic ability tend to hear whispers (from surrounding thoughts via boosted telepathy) just being near it and are intensely drawn to it. Though it doesn't feel like a proper mind, the egg has a "presence" that telepaths can feel when they are in the room with it.
The egg acts like a booster for telepathic powers upon physical contact. Even weak/latent telepaths like Ori are boosted enough to serve as proper telepaths so long as they maintain contact with the artifact. Actually using those powers still requires the same amount of practice and training as a normal telepath, though.