The telescope is actually an artifact called the Farseer of Illusk, implying that it came from one of the ancient civilizations named Illusk (of which there were probably at least two) that preceded Luskan, City of Sails. (See Volo's Guide to the North, the Netheril boxed set, and the timeline in the revised Forgotten Realms boxed set.) Adele has a key that opens the metal box to expose more buttons and levers. After manipulating them in an exact sequence, she can look through the telescope to view anywhere in the surrounding area for a 50-mile radius, just as if it were broad daylight. (Note that Iniarv's Tower is hidden behind natural rises in the landscape and cannot be seen.)

Although it may point to the sky, the Farseer of Illusk actually acts as a wizard eye looking down from below, and Adele can move the telescope around to see various places. Adele uses the artifact to locate travelers on the High Road to the east. When she finds her prey for the night, she goes to her bedroom, casts invisibility on herself, and opens the windows. After entering her closet, she detaches her head which enlarges (per her contingency spell). She then flies out to partake in the evenings blood feast.

PCs who tinker with the telescope can use the exposed levers and dials to move the Farseer of Illusk around and focus it on the heavenly bodies, but determining its magical properties is a different matter. Finding the secret compartment's keyhole is the same as finding a secret door. Opening it is the same chance as opening a lock (or knock would work). Bashing it open destroys the fine gears, rendering the telescope inoperable. Fiddling with the secret levers and dials must be done in an exact sequence, and each PC has a 10% chance of discovering it out by accident (only one try per PC), Identify spells have a good chance of discovering the sequence — 10% per level of the caster — but a roll of 96-00 triggers a defense mechanism within the artifact: Mistress Adele becomes aware that someone is fooling with her prized possession, and she investigates immediately. The next day she tells her followers that the PCs have fallen in league with the vampire, and when they enter the dining area for their next meal, each member of the Academy attacks the PCs with every spell at her disposal.

Once the PCs determine how the device works, they can look around and locate nests of monsters throughout the mere. They also observe the blanket of fog that shrouds the area with a five-mile radius to the east of Castle Naerytar. This is the domain of Datou, the swamp druid. Clever PCs might even focus the view on Castle Naerytar itself, see Datou skulking around, and plan an ambush for him. The device does not allow the PCs to penetrate the fog enshrouding Datou's domain.