Some years ago, in a fairly foul mood at the “wacky Halloween” festivities, I got to thinking about what a real All Hallows Eve would be like.
The dead or demons come into the world; from where? That leads to my version of the Underworld. Why only this day? That leads to ripping off Prince of Darkness. They must be shapeshifters, given the costumes. They like playing with us, given the “trick or treat” choice. So they’re predatory, but at the higher level they’re herding us, they need our fear.
The first time I ran this was in Eden Studios’ Witchcraft/All Flesh Must be Eaten, but it really cried out for a less heroic game, something with a horrible downward spiral. The 3d6 system in this is unkind, to say the least. Damage makes you less and less competent to escape or accomplish anything. Pretty soon you’re just throwing your dead meat in the way of a monster to let someone else escape. Note the Tech rules. That’s your closest thing to magic, the only advantage you have.
Of the 3 groups I’ve run it for, one of regulars, two pick-ups, nobody’s made it to the next day, so the long-term campaign ideas are ludicrous and untested.