MeepoTheMighty said:
428) Let the party find a skeleton key, a rope, and a pistol. Then let them meet themselves from ten minutes in the future and make them give up the skeleton key, rope, and pistol.
The really sadistic 'Groundhog Day' version of this goes like this -
DM: 'you are traveling down a rough-hewn stone corridor, about ten feet wide. Soon you arrive at an intersection. From your right you hear the sound of something approaching, a group of people you think.'
(note player reactions, write down what they did, adjust the following for their actions)
DM: 'The group comes into view and you see that they look exactly like you. (Point to the a player) The one who looks like you exclaims - 'look, its gone!'. Then they notice you. They look momentarily taken aback then (Point to the 'leader' PC) the one who looks like you steps up to you and says: "Look, we haven't isn't much time - take these (hands him the gun, skeleton key, rope and any major artefacts you feel like throwing in there) and follow the corridor straight ahead. Oh, and see you around." They then depart down the corridor opposite the one they came in from. They're about twenty meters down when the passage they've just traveled down suddenly collapses in on itself."
Keep note of anything the players do during this encounter. After it concludes, they will probably head down the corridor directed by their future selves. If not, the other corridor seems to end in a dead end 30 ft down. No amount of searching reveals where the other guys might have come from.
Now, they travel down the central corridor for about 10 minutes. It winds and turns, eventually doubling back on itself and ends in a fairly obvious one-way secret door. If they go through, they find themselves in a corridor with an intersection about 30 ft ahead (the cave-in is now gone). No amount of searching reveals the door they just came through.
Now the fun begins. As they approach the intersection, they encounter their 'past' selves doing whatever they themselves were doing ten minutes back. However, the catch is that they now have to do exactly what their future selves did to prevent a rift in the space-time continuum (Star Trek-style!). The moment they deviate from the exact sequence and wording you described 10 minutes back, the following happens:
DM: As you perform that action, everyone hears a strange ripping sound, as if something being torn apart, then there is a sudden flash of intensly bright light which blinds you all for a moment. When your sight returns, you are traveling down a rough-hewn stone corridor, about ten feet wide. Soon you arrive at an intersection. From your right you hear the sound of something approaching, a group of people you think.
Lather, Rinse, Repeat. Works best if your group is a bit dim (or not trekkies) and doesn't figure out what is going on until they've been through a few times
Yours,
Altin