Isiah's visit to the surface city of Triavert was a strategic and temporary move. The city already had an established system for supervision, with individuals or groups assigned to different areas to report any potential attacks promptly. This suggests a well-organized defense mechanism in place.
Isiah's choice not to linger in the surface city of Triavert is consistent with his primary objective of gathering additional information about the Afan region.
Isiah, after summoning Jafar, employed the spell Abyssus to hide their place in order to travel to the closest city to Triavert .
Isiah's journey to the nearest city took a few hours, during which Jafar exerted considerable effort to expedite the trip.
Isiah had several options for cities near Triavert, including Barka, Ghifl, and Qusda. Despite their proximity, Isiah strategically chose Qusda as his destination.