Voidforge--please explain it to me

[Rankin-shandris (Rankin)]

They explained it in the patch notes a while back:

12.0.5 PTR Development Notes

12.0.5 PTR Development Notes INCOMING VOID ASSAULTS The forces of the Void are vying for position and control amongst themselves in a bid for more power. As they seek every opportunity they can, attacks begin in the Eversong Woods and Zul’Aman zones. Void Strike Void Strikes take part in Eversong Woods or Zul’Aman on a weekly rotation. Once completed, a new one will begin in another part of the zone and continue to rotate through the zones. Void Incursion These larger scenarios occur when e…

It’s both bonus rolls and an upgrade system.