My players, after having travelled through a big Kobold empire to find a temple, finally encountered the temple, only to find it inhabited by a Dragon. They bump into the Kobold who had been tracking their progress after scouting the temple and being concerned about there being the Dragon.
The Kobold ranger outright tells them that the only reason they were allowed into the Empire to look for their temple is because the Kobolds knew there was a Dragon in the temple (even though they never told them before) and they were hoping to manipulate the players into killing it (the Dragon had set up wards that blocked out Kobolds, so they couldn't do it themselves)
The players proceeded to demand a reward in gold and trade-rights from the Ranger, who said that he could promise them an audience with the emperor and that he'd reward them for helping. Why they think this was a good idea is the topic of a second question I'll be asking.
However, this means that during the next session the players will be travelling to a nearby city to talk with the local Kobold Duke of the province that borders the players' own city (the Ranger has no intention of taking them all the way to the emperor, he has stuff to do) where he will leave the players to discuss trade rights.
This empire is absolutely vast, the players control a small city (about 1000 humans) and they basically have nothing to offer the Kobolds. (Well, slaves maybe, but I don't think the players will go for that) The Duke is also not very interested in giving the players the large sum of gold that the Ranger promised them.
However, he will be very interested in manipulating the party further to do his dirty work and maybe get them killed just for the sadistic pleasure the Kobolds will get from it.
But I'm a little stuck on how to properly portray this guy and his advisors. They are all hateful of non-Kobolds (which is something I can play well enough) but they also have to be manipulative and believable, and that's the hardest part.
The players have not seen the Kobolds do anything evil (mostly because they haven't been allowed in any Kobold town yet) but they're very aware that Kobolds are usually evil, are very xenophobic and that the only one they've really talked to has openly admitted to being manipulative towards them.
As a DM, how do I play an evil noble trying to trick the players into doing his dirty work? I don't want to railroad them anywhere, but ideally I want them to accept his offer out of their own free will and play it such that the Duke doesn't have to pay them much (or anything) in the end.
Best Answer
Firstly, it sounds as though your players are doing a lot of the heavy lifting for you in that they are being very easily manipulated without much effort on your part at all. But let's talk about manipulation.
Pa-pa-pa-poker face
Manipulation relies on getting people to do something without them knowing exactly why you want them to do it, or even that you want them to do it at all sometimes. Why? Because if they knew your reasons, they most likely wouldn't do it, and that doesn't help you. So lying. Your duke should agree to pay these adventurers anything they want if they do the tasks required of them. And he will lie. Oh will he lie. He will lie gleefully and to their faces, especially if they are silly enough to just blithely believe everything he says to them.
But what if they don't believe him...
Believable lying for beginners!
The best lies rely on two key concepts.
Let's go through them.
1) The more outlandish the lie, the less likely that someone will believe it. This seems like a common-sense thing, but people have a hard time with it. The best way to lie, then, is to distort or stretch the truth. Maybe the kobolds really do fear the dragon and want it dead because it could kill them all. It just also happens that a dead dragon means its horde is ripe for plundering, but the kobolds won't mention that they plan on taking all of that treasure for themselves. Why bring it up?
And an important thing to remember here: if you're playing someone who is actually manipulative, they will not seem stereotypically manipulative or as though they are lying. No long pauses or sideways glances, no hemming and hawing over details, no emphasizing exact wording ("I won't take your treasure." etc.) Lie. Lie right to their faces. Straight faced and unabashedly. It's amazing what people will buy if you just don't call attention to yourself and your weird behaviors.
2) Appeal to emotions. The players must care about some things. A manipulative person can tap into those desires. If your party is obviously in it for the wealth, maybe the duke talks about all the hidden treasure that would be "too much of a hassle" for the kobolds to dig out themselves, but the heroes are welcome to any of it they find along the way. If the heroes are sympathetic to the plight of the underprivileged, perhaps the thing the duke wants them to do is causing famine or disease, or is hurting the poorest of the community. "Really, it would be better for everyone if someone stopped it, but darn it I just don't have the resources to." Say anything to get them to agree. That's the point.
You lying bastard!
When the PCs do find out they've been had, there are one of two ways the duke can play it. He can try the "it was a misunderstanding" approach if he hopes to manipulate them again, but more than likely he will just be dismissive. He presumably has a contingency of kobold soldiers at his disposal, an army should be more than enough to take care of any PCs. Into the arena pits they go! (The duke may want to ask for more soldiers from his emperor while the PCs are away. He knows he lied to them and knows that they'll be pissed and knows they were capable of killing a dragon.) Don't make it a big show either. If the PCs call him out for his lying ways, he just accepts it. No reason to care what they think, they aren't kobolds and so they are inferior.