Ok this is a long one. 

So last year I was in my friend's D&D game. In this i was a paladin who had a rivilry with a Devil. About 2/3rds in the paladin died and i then played his brother who was a cleric, but one who had strong tied to a powerful organization that was lead by an acnicent gold dragon (dont ask). Now at some point I wanted to trap this devil, who was very powerful, via magic items and really f'ing smart. 

I discussed a plan with the DM on how i would draw the devil out, even going as far as employing the ancient gold dragons help, as well as others. Given the other player's affliation with this devil, i kept the plan from them, but had also come up with a plan to deal with them. They made deals with him, i did not. 

Now me and the DM planned out what would happen, i wrote a very good speech over the corse of a week and even set up a supernatural style devils trap, so that IF the devil took the bate, he would be trapped. But i would be trapped with him. Make no mistake i knew it was risky and the chances of it succeeding miminmal. The whole point of this encounter was to take away a very powerful artifact that this devil had and he mocked the organization that the cleric was apart off.  Now when it came time to execute this plan, the gold dragon was waiting behind the building to where the devil would be lured. The plan was kept secret from everyone, and the looks on their faces when i said the speech was golden. 

The devil took the bate, and stepped into the trap with me inside, the other players, thankfully and rightfully so did not interfer. The dragon did not show up and then an explosion was heard inside the organization's fort. That is when the dragon appered and flew off to the fort. It was his lair. The devil mocked me and the plan at this point, which hindered on the dragon was now gone. So i decidie I would plan shift the devil to Mount Celestia. 

Now here is where the problem actully arises. The devil wasnt there. What was, was a "decoy doll" a magic item that can take the form of it's owner can be used for destractions or divertions. It was THIS part that broke me. After a week of planning, even after expecting everything to get screwed, the devil WASN'T THERE! He was busy stealing from the gold dragon. 

After having a heated debate about this to the DM about railroading me and straight up wasting my time he explained his plan, which to be fair I belive him. He had been planning this encounter for 6 months with my original charcter, but moved onto my current. He bated me into the confrontation, quite brillantly too, to which I fell for it. The DM had used the devil to contact the other two players of the party and asked him to do an errand and borrowed the decoy doll of another player. The earrand, which the player had no idea of, was to return a book to a libary, which turned out to be the explosion. The devil then waited and turend the decoy doll into himself and bated me, while the devil exectued his plan. 

The DM stated that EVERYTHING needed to go right and if anyone thing didnt, the plan wouldnt work, it just so happend that everything went according to the plan. In the end, the devil made off with valubale information and magic item belonging to the dragon, and I made felt like an idiot. Which i was totlly ok with. What got me was the fact the devil was never there to begin with. The DM said i had another NPC to rely on, but i was keeping her for the other plyer incase they tried to stop me. So tacticl error on my part I guess.

What I am trying to say is. The DM keeps saying that the plan could have gone belly up at anytime. As a DM  myself, I get it that they know everything, but the players dont. I had very limited information, and yeah sure, maybe i could have employed other NPC's to help as he stated, but i didnt, thats onme yes. What just got me is that the devil wasnt there, He could have done whatever he wanted, banish me to tiamats pit, tourture me endlessly, you name it, I wasnt expecting to win, but the fact the devil wasnt there and it was an f'ing doll!!!

To make matters worse, when i tried to slavge what i could from the buring dragon lair, I had to deal with a smoke inhilation mechicanic that was sprung on me last miniute. Dispite being fire proof. That matter, i belive has since been sorted. 

What would you have done, was the DM right, or far too calculting? Am i in the wrong?

 To this day he claims he did nothing wrong. Its just that in this situation I learned a messed up lesson. Don't work with the DM, he will screw you over, dispite what he says. The encounter, quite frankly broke me. Again I wasnt expecting to win, I even told him this, but how i did'nt win, just felt Sh**y.

DMs have a tough job. They have to know what the party is planning to make rulings, but then have to figure out if, given what the monsters would know, could the monsters possibly avoid the party's plan? This is not an easy thing to do, and sometimes you just make the call wrong. DMs are human, after all.

Your plan was very involved, and was undertaken against something that is both underhanded/manipulative and highly intelligent. This thing would be working against you while you were trying to work against it. As a DM, trying to solve the calculus of "what would this highly intelligent, evil, and manipulative creature be able to prep against the player's plan?" is not necessarily straightforward, and not every DM would come to the same conclusions.

What the devil did does not seem beyond the pale to me, in terms of its capability and planning (not knowing the actual identity of the devil, its stat block, or anything like this). However, I'm going to be honest here and say that I didn't follow your story 100% -- some of it was a little confusing.

Quote from BioWizard >>

DMs have a tough job. They have to know what the party is planning to make rulings, but then have to figure out if, given what the monsters would know, could the monsters possibly avoid the party's plan? This is not an easy thing to do, and sometimes you just make the call wrong. DMs are human, after all.

Your plan was very involved, and was undertaken against something that is both underhanded/manipulative and highly intelligent. This thing would be working against you while you were trying to work against it. As a DM, trying to solve the calculus of "what would this highly intelligent, evil, and manipulative creature be able to prep against the player's plan?" is not necessarily straightforward, and not every DM would come to the same conclusions.

What the devil did does not seem beyond the pale to me, in terms of its capability and planning (not knowing the actual identity of the devil, its stat block, or anything like this). However, I'm going to be honest here and say that I didn't follow your story 100% -- some of it was a little confusing.

 TBH I'd say you got enough of the story. What part you were confused with?

Given the other player's affliation with this devil, i kept the plan from them, but had also come up with a plan to deal with them. They made deals with him, i did not. 

This part confused me. What other player's affiliation? Did another member of the party have a devil as a patron, say as a warlock? If not, what sort of affiliation do you mean? Also, use of "them" is confusing here. Was this one other player, and you are using a gender-neutral singular pronoun rather than saying "him" or "her?" Or do you mean that several players in the party have an affiliation with the devil, and you are keeping the plan secret from all of them? In short, I could not determine if you were setting up a plan with the DM that was working against not just the devil, but also one or more members of your party, and if so, how many members?

The dragon did not show up and then an explosion was heard inside the organization's fort. That is when the dragon appered and flew off to the fort. It was his lair. The devil mocked me and the plan at this point, which hindered on the dragon was now gone.

This part... I do not understand the sequence of what happened. What was the devil mocking you about? That your dragon, who you thought would help you, did not help you? Where did the dragon appear, before flying off to the fort? I have a lot of trouble picturing what the scene actually was.

Based on later text, it sounds like maybe, perhaps, the dragon was not there because he had sensed the devil messing with his treasure and went off to protect it but, your description is not chronological and so I could not truly make sense of what happened.

Ok so in terms of affiliation, the other players had business dealings with the devil. As in, you scratch.y back, I scratch yours. No patron. There were 2 other players in the session. Both had no reason to turn on the devil. 

As for the dragon, me and the DM did a very short, quick one on one session were I contracted the dragon. The plan was that the dragon would wait outside the building until I trapped the devil, then he would come in and deal with him. The devil would have been no match. But the devil used some kind or time spell on the dragon, basically freezing him in place. Until it was too late. 

All of this really hinges on how plausible it was for the devil to be aware of what's going on and staying a step or two ahead. We don't know what the DM's rationale was for this, so it isn't fair for us to say how it went down shouldn't have been possible, was only a bit of a stretch or really made complete sense. Highly intelligent antagonists with artifact level items at their disposal should be able to pull off some very impressive plans though - I certainly wouldn't assume it to be impossible .

I will say this though: with all due respect, thinking of this as the DM "straight up wasting my time" isn't conducive to having a good game. I assume you had fun seting up your own plan, and were excited to see it play out. That it failed shouldn't change that (especially if the DM had his own plan in motion for six months already, as I'm getting from your post). You'll get another shot at that devil - I'd be psyched about the grudge match. 

What bothers me about the entire story, although I have seen essentially the same in too many other campaigns, is that a devil is able to so directly act on the prime material plane at all. 

I don't disagree, thematically.

However, it seems from the story that supernatural beings are acting directly in this campaign. So I don't think it can be argued that somehow the devil's actions were violating the internal consistency of the world as the DM has been playing things.

I think this is a tough call. The DM thinks he was acting fairly on behalf of an otherworldly creature who is clever, devious, capable, and competent. The player thinks the DM "metagamed" on behalf of this being, giving it more knowledge than it should have had in-character. This is very hard to judge from a simple (confusingly written) 1-page summary provided only by one of the two parties involved. We don't have the DM's side of it at all.

To the OP:

In the end, I think, as a player, that you kind of need to let the DM have this one. You said up-front that you were fully prepared for this to go sideways or completely backfire, and you also acknowledged that the DM had "gotten" you with a bit of a long game on the part of the NPC. The DM's job in this case is a very difficult one -- how to challenge the player and make the devil an appropriately challenging foe, while also facilitating the player in making a plan against that NPC. I think sometimes we underestimate just how hard it is for the DM to do things objectively here, when there almost is no objectively right answer in the first place. You might want to take a step back, and acknowledge just what a tough position you put the DM into, and that he resolved it in the only way he thought he could, and even if maybe it's not how you would have resolved it, give him the benefit of the doubt and let it go.

I know, it's not exactly what you wanted. But DMing is a tough and often thankless job. Your DM was trying to balance some people who wanted to make deals with a devil, and one guy trying to kill it, and had a party in which players were keeping secrets from each other at the table (apparently) which is always hard to adjudicate. I would cut the DM some slack and let it go.

Part of being a DM is maintaining trust with your players. Shocking twists can have a huge payoff, but when you overstep you get this:

 Its just that in this situation I learned a messed up lesson. Don't work with the DM, he will screw you over, dispite what he says. The encounter, quite frankly broke me. Again I wasnt expecting to win, I even told him this, but how i did'nt win, just felt Sh**y.

If my player felt that way about what I did, I would call that a failure on my part. OP is obviously really invested in this struggle and put a lot of work into his plan. For that to culminate in "you get nothing and the devil actually stole even more stuff from your team" is just... I mean what message is that supposed to send? Don't even bother trying because you'll never win against a DM devil with infinite power?

There are endless ways this could have been a partial win or a partial loss that would have been just as dramatic and far less demoralizing. I'll say it - having OP's thoughtful and thorough plan result in a complete and utter loss is objectively bad DMing. And throwing up his hands and saying he can't help that everything worked out just right for his NPC in his world where he controls literally everything is ridiculous. It's the DM equivalent of ruining your teammate's day and claiming "that's what my character would do."

I'm not saying he's a horrible DM and I'm not saying OP should have won that encounter. But I agree with OP that the DM made a mistake there and it will take a lot of time and better decisions to repair the damage done.

I wouldn’t say the DM did anything wrong here - sure, they could have handled things better but DM’s job is already hard as it is and gets exponentially more difficult in situations like this with players keeping secrets and working against one another. You say you were prepared for the possibility that your plan won’t work but it looks like what you actually wanted was for your trap to work perfectly and then maybe some complications arising afterwards - as it was the devil saw the trap coming, outsmarted you and just pretended to bite the bait (at least that’s what I understood from this confusing description) - which is perfectly feasible to me - devils are much more better at scheming and deception than mortal after all, they’ve done it for much longer, it’s not a stretch to think that what seem like a very brilliant and clever plan to a character is child’s play to a devil who had centuries to work his schemes and plots. That said, if you aren’t having time playing you should raise that with the DM out of game, the most perfect story means nothing if the players aren’t enjoying it.

Did the DM truly have the doll ruse planned all along or was that created in the moment by the DM to thwart the elaborate plan that was explained to the DM? There'll always be that nagging question.

I would coin private conversations with the DM about how to plan an encounter before it actually happens to be called "pre-game" - gaming before even playing. If I were the DM, I would have nipped it in the bud and requested to save it for the table. It is my job as DM to be prepared for the players, not prescient about the players.

The same goes for players. Players should never expect prescience of events that are intended to play out on the table. There's little risk when one is certain of the possible outcomes.

I would not invite such expectations as an DM, and as a player, I would not try to hedge bets with the DM, either. The former will feel unfair to the players and the latter is unfair to the DM.

I think the lesson should be: Save it for the table. Both the DM and player need to understand this.

Quote from EricHVela >>

 

I think the lesson should be: Save it for the table. Both the DM and player need to understand this.

That's a very reasonable notion. I don't know how much it'd have helped in this case, however. Whether this plan was set up in private with the DM or the interactions were played out at the table, the DM would still have known the details before it actually enfolded. Creating the trap and enlisting the help of the golden dragon and others aren't things the player can just declare to have happened out of the blue. They need DM involvement in some way. 

As far as I can tell, the reason for the way the player handled things is wanting to keep the other players out of it. It was about an effectively split party and metagame knowledge. And honestly, that sort of thing can be very effective and fun. It's not something you need to have in every campaign and probably isn't something that should be planned ahead, but if the campaign evolves in a direction where this sort of plotline occurs spontaneously it can be a lot of fun to see it through.

Quote from EricHVela >>

Save it for the table. 

 This. Right here. I think that the DM was put into a spot where he HAD to counter the plan at least in some form. I overall think that plans need to be saved for the game. I have a player who loves to make elaborate plans, and I let him do it as long as it’s in character. I just don’t want to hear about it when it’s not during the game. Because then if I heard it out of game what should I do? I have to let the plan succeed by meta gaming and catering a free victory to the player which the rest of the party would be left out in the process of giving the victory or pseudo-metagame out of the plan and result in a failure or at least a partial failure. I won’t say the DM has handled it super well, but you’ve put the DM in a tough position. I wouldn’t really blame you, you just had a hype plan you wanted to share. So the moral of the story as said above, is to save things for the table. This doesn’t mean players shouldn’t always plan with the DM as I’ve heard of some great stories where that has worked out amazingly, just you need to know when to do it.

"Rocks fall on you and you die".

DM's can pull this at any time and they don't need crazy convoluted plans to do so.  But our players trust that we won't because it's unlikely to be fun for them if we did.  A few people commented above about the whole trust issue and I think that's the most important part of this.  A good talk between player and DM about what everyone wants out of the game is important.

In some groups saying "I expect that this will fail and the demon will outsmart me" is an invitation for the DM to do exactly that:  find a way for the Devil to have outsmarted him.  On the other hand in other groups, that line is code for "I really hope this comes down to some really intense dice rolls and that I win with 1 HP left.  In either case, the players and the DM all have to trust each other and respect each other as story tellers.

Did the DM truly have the doll ruse planned all along or was that created in the moment by the DM to thwart the elaborate plan that was explained to the DM? There'll always be that nagging question.

Well, I hope it's not a nagging question. If the DM said, "I had been planning this all along," then I hope you can trust your DM that this is the truth. The DM shouldn't lie to players like that. 

The DM has every right to be coy, of course... Player asks, "This was the plan all along wasn't it?" DM responds, "Well he's dead now, so I guess you'll never know..." Or what have you. Sometimes I tell my players what I was thinking or share my logic with them, but only when I think it won't break or destroy immersion. Otherwise I just stay silent.

As a DM, I work hard to keep myself as honest as possible, and one way I try to do that is to write out notes to myself on "what the monsters will do if..." For example, my party is right now exploring a shrine full of hundreds of Kuo-Toa, including many guards. For each guard post, I wrote out what they would do if they saw "warm bloods" in their shrine. When the party started attacking some of them, I had the K-Ts respond the way I had already written down in my notes. Now things changed, and the situation morphed, and then I had to start logically thinking about what the K-Ts will do next, in response to hearing 3 fireballs go off in a matter of less than a minute, for example. But as a DM, my goal is always to try to fairly judge, what would the monsters do in this case? Not "can I foil the players' plans."

My players can message each other without me seeing it, and maybe they sometimes do. But I don't think they do it much. Usually when they are doing a group email about what they plan in the future, they CC me on it. I assume this means that they don't think I will cheat and have the enemy thwart their plans just because I, the DM, know them.

Sounds like your DM played the Devil as a cunning, intelligent, and powerful adversary who used everything in it's power (including your party?!) to best you. I'm sure it's frustrating, but sometimes the heroes plans fail now to succeed later.