After the discovery of the First Gate scientists and archaeologist’s were dispatched to discover the origins or purpose of the structure. It was noted, as more Gate discoveries came to light, that each, of the seven different worlds, was dependent on the others. Together they created a balanced environment suitable for life to thrive. For one world to be stable the others were necessary. This came to be known as the Sevenworlds Condition.

Excerpt from Sevenworlds and The Gates by Berim of Allra

THE UNIVERSE

Outer World (aka Earth, aka Seventh Ring)
Odd World (aka Rov, aka Sixth Ring)
Third World (aka Merdia, aka Fifth Ring)
Midway World (aka Odren, aka Fourth Ring)
Halfway World (aka Briea, aka Third Ring)
Second World ( aka Cedal, aka Second Ring)
Inner World (aka , Pelus aka First Ring)