heh | January 22, 2016
Soo this plot point is actually calling allllll the way back to the very beginning of the story
, to an incident the mages' guild has been trying very hard to suppress or at least feign uninvolvement with. They dance around the subject in every scene where the orb comes up, and the one positive aspect to Viraigo's involvement with the whole affair for them has been to give them a convenient scapegoat.
As for why Teeko's so upset, her background is covered in chapter 2, specifically starting with this scene.