Add the following events on Halloween:

• The normal “midnight” effects should begin at 6 PM.
• Intelligent monsters may generate peaceful and with candy bars, which they will give to you when you chat to them. Or possibly, this only happens with monsters that have “homes” such as shopkeepers, priests, and peaceful Minetown inhabitants. (Not specified what happens if a monster generates with a candy bar, but you save the game and come back to talk to them once it’s no longer Halloween.)
• Other monsters have a higher than normal chance of generating with attack wands.