Orb of Souls

The Orb of Souls is one of the nine Tears of the Prophets, taken by the Cardassians during their occupation of Bajor, and eventually returned to Bajor in 2376 along with three other orbs, thus returning all nine Tears to Bajor. According to Opaka Sulan, the Orb of Souls is the least understood of all nine orbs, and encounters with it are also more tasking than any of the other orbs. Not many willingly look into the Orb of Souls, though it has been known to 'call' to individuals as a sort of summons (Star Trek: Deep Space Nine - Fearful Symmetry).

An unknown number of centuries prior to the Cardassian Occupation, a Bajoran Kai named Dava Nikende was called to the Orb of Souls. In January of 2377, Benjamin Sisko encountered the Orb of Souls upon being summoned to it. His encounter led him to a setting similar to where he had previously spoken with the Prophets, but where he now met with seven other Benjamin Siskos, each from a different alternate universe (Star Trek: Deep Space Nine - Fearful Symmetry).