Well, you could play Pendragon RPG, a system that explicitly rates each character's vulnerability to different character flaws and passions. A Pendragon knight beset by an unearthly vision of lust would roll a 20-sided die, check his character sheet, and either succeed or succumb. In service of a more picaresque story, a Dying Earth RPG character might be overcome by a persuasive flourish and be compelled sit down at the gambling table with a known master swindler.
Temptation is part of those games' moral mechanics. It's not part of most other games, though. You may have alignment, or resistance to mental influence, but nothing stops the characters from making choices like perfect Puritanical optimizers, every day of the week. Except maybe under "carousing for experience" rules, which kind of proves the point.
As I threw wave after wave of diabolical tempters at the party on the last two nights of their ordeal, defending the praying penitent in the Devil's Acre, a number of options arose:
1. Have the tempters target the NPC penitent; the PCs have to stop them from getting into range and distracting the penitent, and the tempters will fight to get close. If the blockade fails, then being an NPC, the penitent has to make some kind of save or check against the temptation.
|Um, yeah, just like that.|
3. Note the past behavior of the PCs and their allies, and use this to direct the efforts and outcome of strategy #2. It's not a matter of rolling a die, but of having raided a merchant ship for its treasure four sessions ago, so Avarice already has its claws in you. This makes the most sense if sin pays in your campaign, at least temporarily; for example, if spending gold on carousing nets you more experience points than donating it safely to a church does.
4. Target the players. I need to explain this some.
In the past here, I've argued for drawing on the concerns and tendencies of the players themselves to stand in for such traits in their characters as alignment and morale. Obviously, this won't always work. Some of these theological sins refer to the satiation of bodily needs: lust and gluttony in particular. All right, there were some pretty delicious chocolate and banana cakes on the table at our session, and I could have worked them in somehow ... but yeah, and then lust, no, yeah, forget it.
Other of the theological sins, however, serve the needs of the ego, the little character we all build for ourselves. I don't care if you don't play D&D. You are still walking around with a "character sheet" in your head, with some idea of your skills and abilities, where you fit in the hierarchy of things (level) and what road you walk in life is (class). It's part of the undying psychological appeal of role-playing - to create a character on paper more free, more disciplined, more interesting, more dramatic, than the one in your skin. But when you role-play, the two egos become one, as you defend the interests and dignity of your character.
With these other sins, to attack the character is to attack the player, whose ego is the character's ego. Wrath? Touch upon the player's need to avenge harm done. Avarice? Throw loot at the player - or better yet, threaten to take it away. Envy? Make the player feel unfairly disadvantaged; take away some experience points and give it to the next guy. Pride? It's what makes them go "Let me tell you about my character..." Work with it.
All right. In the actual Devil's Acre session, some of these ploys worked better than other. Next post: a play-by-play of the seven-round knockout the Band of Iron dealt the Prince of Darkness.