Not far from Yaraq, I found the entrance to Under Cove Crypt, which has a portal restricted to levels 5 and up. A locked metal door barred entrance to the portal, but a scrap of parchment on the ground provided a clue.
Intriguing. Perhaps the strange, purple light above the tower is the "star" described in the parchment? It would be fun to gather a party and explore...if we can get past the drudges in the tower.