Pyramid of Shadows - a path ahead.
-- Recap of events up to now--
Through use of the Rod and the powers that it bestowed Paldemar, along with tainting his mind and actions, he sought to capture and create a rift to the shadowfell.
As the veil is thin between The Nether vale and the shadowfell, piercing it from within the Thunderspire Labyrinth and using the lore and abilities of the mighty mage Karavakos and his artifact allowing the capture and opening the the rift, allowing Orcus, his influence and minions to freely ascend on the lands and cause eternal darkness and anguish.
Failing the ritual to bind the rift and succeed in dragging a fortress of necrotic energy back to this plane, the fabled pyramid of shadows, forces have now sought to not only find other ways to bind and force it through, albeit from the other plane, but also seek vengeance and revenge on those who stand in the way and prevented it.
As a shadow and agents of Orcus and the pyramid begin to come through, albeit little at the time, and harassing the city of Fallcrest, the concern is that the mission to stop Paldemar and the veil in the sea of shadows, have been no more than a delay to something inevitable - and the heroes, the group, have every chance to gather, and prevent this by dealing a final blow to the plan and damnation of the lands.
The mages, instrumental in being caught and bound, know the above and parlays it to the group - and points to fallcrest as a key location to stop any agent of Orcus and their enemy.