Kallyrs Stationary Lightbringer Quest was much like how many people understand heroquesting. She got the tribes and temples to perform a giant ceremony filled with pageantry. People wore masks and sacred regalia and tried to carry out their sacred tasks as Kallyr and her companions moved around Sartar performing their reenactment of the Lightbringers Quest myth.
Spirits and people were summoned from outside. Yelmalion cultists showed up as did trolls and some elves. Others made sure the dragonewts did not enter. Monsters appeared and weird foreigners arrived. Broo and zombies both tried to exploit opportunities.
By performing it in this way, such foes could be confronted and defeated. And for the most part they were. But nobody expected that Jareel herself would be able to use the ceremony as a beacon and gate, to appear at the climax of the ceremony and disrupt it so thoroughly. The dangers of the Lightbringers ceremony were revealed to all and nobody tried to make a similar use of it for another 20 years.
As a game event your player might find themselves aiding Kallyr, testing her, or dealing with the weird stuff summoned by the ritual.