PrinceCon VIII - The Great Murder Mystery
How did Emperor Zorrel get assassinated, given all the protections that were supposed to make him practically immortal and invulnerable? The solution to the mystery took most of a page just to name all of the elements involved; one of them was a kryptonite (!) dog collar. Every GM had one red clue (major) and several blue clues (minor) to give out. Many were red herrings; a group of GMs read every clue that the 4 of them were given on Sunday and had nothing that helped with the solutuion. The winning player who solved the mystery practically never left Hireling Hall, because it was so hard!
The end solution was that the evil lich Sharpac had killed him with a death spell that got through because of [list of circumstances lost to the sands of time, though P. Mayewski recalls it had something to with seeing a man about a missing dog].
PrinceCon VIII was the first year we tried differentiating religions in terms of game mechanics. There were two colors, one to indicate alignment (Good, Neutral, Evil, Chaotic) and one to indicate a god. Followers (with the same choice of color) got +1 per die on cures.