Is the bad ending an option or is it predetermined? If its predetermined then it will be apparent and your players will feel cheated and that they wasted their time. Under those circumstances I wouldn't game with you again.

If it ends in TPK resulting from their actions then they will be disappointed, but that happens from time to time in role playing and I am sure they will be more than willing to push on to something new without any ill feelings.

Quote from: KrakaJakThanks for the feedback, I'm thinking of having a possible bad ending for my current campaign.
Another quick question for those that have...How did you structure it so the players didn't feel let down...or that their Month's of gaming was "wasted"?

I once ran a one-shot where different PCs from different organizations in my game world came together to try to find out why a stolen airship went down over a swamp. Of course, because the organizations were locked in a Cold War scenerio, each had other agendas, often conflicting with another groups. (for example, one had "Recover the Blueprints for the airship." and another had "Prevent anyone from getting the Blueprints." and "Return the Blueprints intact.")

Groups got points based off how many objectives were completed, so in the middle of this kind of combat-ty swamp mission, each unit was politically fighting or slinking around to make sure they got what they wanted. Amazingly enough, though, there was no inter-PC combat! Very stealthy, and a lot of fun, though I'd rebalance the whole enterprise if I did it again.

Definately an option. The series ended just last nigh actually. It was a lot of fun and I didn't have to run with the bad ending.

These are some great ideas for future planning though.