More specific citation attribution needs to be added. "Excelis Saga" is not a story you can use as a source.
The Relic was a device that was powered by life energy and could affect souls.
Jolene's people created it to destroy a war queen whom they were fighting. They knew when her fleet would pass near Artaris and that her sensors would not detect a weapon powered by life energy. They got Iris Wildthyme drunk and brainwashed her so she would take the Relic to Artaris thousands of years back so it would charge with a sufficient quantity of energy to destroy the queen.
However, after Iris did so, the Relic was lost and passed through various hands. Snyper eventually found it and tried to kill everyone on Artaris. Once that happened, the Relic would detonate. Bernice Summerfield and Iris were able to prevent this and the Relic became dormant after that. (AUDIO: Excelis Saga[which?])
The souls of anyone who died on the planet it was located would pass through the internal dimensions of the Relic, leaving a fragment. The accumulation of energy would lead to it being a potentially devastating bomb. (AUDIO: Excelis Saga[which?])