Sheriff Hemlock agrees to close the doors and appoint the guards against the possibility of something escaping the catacombs, until you regroup and come up with a plan to get the quasit or hand him this task. He wants to know it's his problem as soon as you know it is. Until then, you are welcome to try whatever means you come up with and may be accompanied by up to two guards on your request. Anyway, the success will mark up your reward. The Sheriff says that maybe sage Brodert Quink or Ilsoari Gandethus of Turandarok Academy may know more about quasits, or maybe Chask Haladan has some book about them in The Curious Goblin, the local book shop.

As far as Adalbert knows, goblins do not conduct large scale warfare. The most you can expect from goblin troops with goblin leadership is some sort of major semi-organized skirmish. Hobgoblins, on the other hand, conduct large scale warfare just like humans do, or better.

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There is quite a number of NPCs in town with whom you have not yet met. Some are not relevant, some may be relevent. Describe what you are going to accomplish and how you plan to approach that and I will introduce you to them if appropriate. It's still before noon now.