While hunting down the rogue Black Lantern agent known as Lucan, the adventurers were tracking down leads in the Gnomish city of Trolanport.
A coastal city, many waterways thread through the streets, with bridges frequently crossing the rivers and canals. While looking for an informant in the warehouse district, the group was attacked by Sahuagin, a barbaric fish-man race who often raid coastal settlements. While overt attacks against large city environments are unusual, this particular raiding party was looking to capture exceptional trophies as part of a coming of age ritual.
The adventurers were able to easily turn back their attackers and continued on to find their own target.