This is a follow-on module to Corrupted Artery. There are a few things I like about the module, hence the 4 stars (a module has to be iconic for me to give 5 stars).
First, there is something for every character type. There's definitely combat, including a potential duel to gain the favor of folks who can really help Glister. There's also plenty of social interaction encounters for bards and other face characters. Magic types will definitely find their place in solving the dilemmas the city must deal with.
Second, the characters end up performing a multitude of roles. They start by gathering info and support. Then, they train the townfolk in a last minute effort to shore up defenses and ready themselves for the horde. Next, they perform a potentially perilous recon mission into the mountains. Finally, they take their stand as staunch defenders.
Third, the story is open ended enough to allow for a lot of creativity. I DMed this module for three different groups: 1 playtest and 2 at SCARAB. All three groups came up with different ways to solve the various issues as well as choose different methods to stand in the gap for the city. A combat heavy crew attacked things head-on. A magic heavy-one used that magic to bypass encounters and accomplish the mission. A more traditional group did a mix of both.
I do plan on running this module and its predecessor, Corrupted Artery, again on occasion.