Apropos of a discussion on G+ started by John Williams of starting a D&D campaign with the characters being the henchmen and hirelings of a high-level group of heroes and a suggestion by Ed Hackett that play begins after a TPK of the high-level heroes I think a scenario like that might be a fun 0-level DCC funnel if they were trapped far down in a dangerous dungeon. Even in straight D&D it might be interesting to run it as a survival horror-style game where the players started with 2-4 characters each so you don’t have to pull the punches to keep it from being a TPK in the first few minutes of the game.
I think they need to be stuck somewhere hostile, otherwise I’d expect them to just run and the whole thing becomes nothing more than the back-story of how they met. If I did that, though, I’d probably bend over backward to make sure that it was designed so that every trap and every fight was avoidable if the players are careful enough. E.g. Random encounter would have a “tell” depending on the kind of monster, either something that would alert the players the monster was on the move, or that the area was infested with them and they need to seek another way around, or maybe the monster moves by a strict schedule.
Time, encumbrance and resources need to be a big thing since pretty much the whole point is that no fight is survivable (though no fight should be a one-round TPK either, unless that fact is telegraphed well in advance), but there need to be ways to replenish those so that it’s interesting pressure not an inexorable no-win scenario. In fact, if you ever get to the point where given the current situation it’s impossible for the characters to survive and escape, you should probably just call it instead of playing it out ’til the last character drops.
I’d be sure to use all the rules like unintelligent monsters being distracted by food, intelligent ones by treasure, individual init plus whoever retreated last turn automatically wins init so that in a pursuit at least some of the party might get away if there’s a chase, monster reaction rolls so that they might not always be interested in a fight, factions the players can try to ally with, etc. Basically everything that I can to give players a chance to retreat from a disastrous encounter without turning it into, no problem if we find something that’s too dangerous we’ll just run and repeat that until we’re free of the dungeon. Each time they find themselves in over their heads should have a chance of a cost.
The dungeon would need multiple routes through it, and spaces that are definitely safe to hole up in and rest…at least at certain times and if precautions are taken. And if possible, I’d probably try to make it so that all the “dungeon dressing” was meaningful: everything is a potential clue to survival, either providing information about the inhabitants of the dungeon, what’s in which direction, where resources and allies might be found, or something that could be used as a resource, like maybe you can use those charred bones to mark your way or as fodder to distract an ooze. The meaning of the info might not be readily apparent, but I think it would be good to avoid complete red herrings and bizarre random stuff that’s just to provide atmosphere. In a normal dungeon that kind of thing is fine, and gives the players’ imaginations something to chew on besides fighting monsters, but the players can choose the balance they want between the risk of missing something and the tedium of investigating meaningless clues, since the penalty for ignoring a clue is usually not very severe: a missed opportunity to find a short-cut or hidden treasure. In a dungeon where there’s a risk of TPK for any ignored clues, it strikes me as a real drag on play to make the players spend time sifting out the red herrings.
I don’t know if my home-group of players would be too into this, but it might be fun to try as a hangout game.
You could give them a detailed “Map” of where the higher level PCs have already gone, with notes. These clues could help the players find a way out. They got down there so they should have some knowledge of the dungeon, the map could be the best and most exciting way of doing that other than telling them.