Neverwinter Nights Guides & Walkthroughs
An Excess of Prophet is a side quest that begins by speaking with Haniah inside of the Community Hall building in Hilltop. Haniah can be found next to Mayor Veraunt Shuttlescomb, she does pretty much all of the talking for the drunken mayor. For this side quest you're tasked with getting the doomsday Piper to leave town - preferably peacefully.
You'll find the Piper outside of the Community Hall next to the gate connecting West and East Hilltop. A screenshot of the Piper is shown below so you know who you're dealing with. It's strongly recommended that before you speak with him you save your game because it's easy to mess up your dialogue with him and put yourself into a situation where your only choice to finish the quest is to kill him.
The easiest way to convince the Piper to leave is by successfully Persuading him with the, "I think you have done all you can for the people of Hilltop. Others need to be warned" dialogue option. If you fail this Persuade check there are 2 other approaches you can take to getting the Piper to shut up.
Keep talking with the Piper and you can eventually blame him for the crime of desecrating the bodies. This will result in the Piper saying the wrong thing and sickening his flock which makes them lose interest in him. Alternatively, you can bring up the Piper's sword in dialogue and offer to retrieve it for him - this will also solve the quest.
If you have to play fetch and retrieve the Piper's sword you'll have to visit Fiona the blacksmith and buy it from her or take it from her. Regardless return to the Piper and give it to him and he'll denounce the gods and be on his merry way. Now all that's left is to return to Haniah in the Community Hall building and complete this quest.