To recap, “Aragorn” (or rather, the total dumbass playing him), despite every possible warning and foreshadowing that breaking his word to the Dead Men of Dunharrow would be a mind-bogglingly bad idea (that’s never stopped him before), he strongly considers it before being talked out of it by the rest of the gamers.
So two questions: What would have happened in the original story if Aragorn had in a fit of insanity gone back on his word? And what do you suppose the DM in the game would have done if he couldn’t get Dumbass to reconsider?
I could see Aragorn saying, “I’ll release you from your oath, I absolutely positively guarantee it, but only after you help me storm Mordor and overthrow Sauron. The job’s not done until then.” The King of the Mountains might or might not be assuaged by that promise (but I suspect not).
The Dead Men might also kill everyone in sight except Aragorn, and thus sarcastically argue that they had not failed in their duty to Elendil’s heir - but only him.
If I were the DM, I might have the Dead Men draw their swords and head back into Minas Tirith, obviously about to start killing civilians, in order to prompt the Aragorn player to say, “You know what? You’re right. I release you from your oath. Get outta here.”
He would not have been able to - he set the conditions at the Stone of Erech before they accompanied him, there would no way for him to retain them when the oath was fulfilled (remember that in the book, the Dead just clear off the Corsairs, they have no part in the Battle of the Pellenor Fields - I read that as them only having to clear the enemy out of their own territory, as per the original curse) . He could have said “Wait, you have to stay” and they would be all “Whatevs Bub, Oath fulfilled, we out” - Aragorn isn’t casting a Dominate Undead spell on them that he has to consciously release, like some DnD cleric. He’s just fulfilling the conditions of a curse - he’s saying this one task fulfils it. He has no power over the Dead beyond that.
If I were the DM, I’d play it like that - the Dead would just say “Fuck you, we’re off” and that would be that.
Yeah, leaning towards “fuck you, we’re off.” It was pretty clear that what they wanted more than anything else was oblivion, and I can’t imagine they would delay that a moment longer than they had to, even for vengeance or to make a point to an impudent Aragorn.