When Nocturne and the echidnas of the Nocturnus Clan were taken into the Twilight Cage, they all heard a voice in their heads saying something like "Argus". Imperator Ix came to calling this event the Argus Event. Nestor the Wise theorized, based on information from the Precursor Tablets, that Argus may have been the entity responsible for bringing not only the Nocturnus Clan to the Twilight Cage, but also the other resident groups: the Voxai, the Kron, the Zoah and the N'rrgal.