Blue Orb Mystery in Arcane Sanctuary

This is a mystery/game secret/possible easter egg that has yet to be solved. Upon killing all the Lightning Spires in Arcane Sanctuary, after the last spire is dead and remains behind, it accumulates a blue orb on top that builds up after a player hasn’t visited that near map area. After spending a short time, the blue orb disappears. What is the possible meaning and purpose of this? What possible secret adventure does this have?

Unlocks ploot and p8 online! hopefully keeps those people busy for a few years instead of creating 12 more threads…thank you Leviathan your feet are not made of clay