What a devil wants

[TarionzCousin]

Lots of great answers here. Thinking about them leads me to ask you what you want to accomplish/what will the end result be?

Most of the responses add potential fun, make the PC's lives difficult, mix it up a bit--pretty much what you would expect in a D&D game.

If you want to raise the stakes, do something like post #10 proposes and make fulfilling the promise nigh-impossible. This may, of course, result in a dead/removed from game character. That might be too much or it might be awesome.

 

[Grogg of the North]

Well, to be honest, it's half thought experiment and half "Having an card up my sleeve to abort a TPK".

In the game I'm DMing, there is a devil fight coming up that happens right after a series of tough fights. It's winnable if the PCs are smart. But we all know that players can be thicker than mud. I wouldn't put it past my players to try and barter with the devil to save their own skins. So I wanted to be prepared just in case.

The advice here has been invaluable. I definitely think I'll be asking for favors that are either nigh impossible or deceptively simple. And they all definitely favor the forces of hell.

 

[Bkeats]

Oh, I agree, but it's totally antithetical to a devil's mission in life to leave heroes largely free to take their own actions. Yes, they prefer to assimilate, but if they cannot dominate, then they prefer to destroy. They will not leave things up to chance. They will not leave things free. Freedom, chance, randomness, these are things as hateful to them as charity and mercy. If there is any doubt as to whether they will win, they will certainly prefer the surety of destruction to the potential of corruption only. They only play rigged games that they cannot lose. That's why you never bargain with a devil. The DM in this case should rig the game so that he thinks there is zero chance of the PCs winning. If they manage to escape fate anyway, fine and good. But this is no time to be fair about it.

ADDENDUM: Imagine it this way. That devil is reporting to another devil at least as ruthless and cruel as he is, and that devil demands results. He has to make an account of his every action. That devil will pore over his every decision, criticizing every fault he can find with it. If it doesn't live up to his supervisors standards, if anything goes wrong, he stands to face eons of unremitting torment. While it's true he can win greater esteem from the hierarchy for assimilating some heroes to his cause, if there is the slightest chance that would go wrong and along the way the heroes will in some way thwart the designs of hell, or make him to look foolish by outwitting him, he will always prefer to cover his own rear by just killing dangerous potentially uncontrollable heroes than taking a risk on a bargain he might not win and which might result in as much good as it does evil.

As usual, Celebrim gets it right. Devils don't like taking chances unless they're forced to by desperation. Faustian bargains are normally their tool of choice for corruption, but by the rules you can't force a creature to sign one by threatening it with death or harm if it doesn't. In the initial example, the devil has already defeated the players, so unless it thinks it can persuade them to the side of evil, it'd probably just kill them unless they're worth more as living prisoners in the Bastille of Flesh or some such place. Devils are constantly doing cost/risk analysis