| Leonai |
It seems like the group as a whole made a really stupid mistake. It might be a bit unfair to single out the paladin at that point. My suggestion is to have some angel or NPC point out to the party as a whole that what they did was really bad for the world, and that as a whole they should feel obligated to stop it. You could even make it a new plot hook or something(although it looks like the group has put the scenario. The paladin should feel particularly bad -he made a mistake- and should receive a vision from his deity warning that the fiend is now his responsibility- but he shouldn't be singled out as a whole for what was basically party stupidity- the group should probably pay with him.
Having played a paladin before, it always put me in a difficult spot whenever another member did something really, really stupid or evil (one I often couldn't stop, and the few times I could, found that it always created drama afterwards). I know as a paladin, the code of conduct (at least the earlier versions) prohibits associating with evil people, but as a player I don't want my character to become the self-righteous jerk always telling people what to do (though there should be opportunities where players can roleplay dissent or disagreement), I've seen that cause as many problems as a paladin who doesn't try to play his alignment as all. In that scenario, I would have tried to insist to the group that the runes should be read first, but if a party member had opened it anyway, I'm not sure I would have acted any differently than that particular paladin: fight until we're obviously outmatched, save anyone we can (even though I'd really want to kill the idiot who opened the door) and not believe that the demon would continue to avoid unconscious party members.