D&D 5E Tracking undesirables

[The Crimson Binome]

Zone of Truth is highly reliable in this edition. It lasts for ten minutes, and they have to make a save once per round, with a single failure preventing them from lying for the rest of the duration. You could either trick them into standing in the area for a minute, before confessing that they have no ill intent (and don't plan on that changing for the duration of their visit), or you could make it a formal procedure for all guests to the castle.

 

[Eltab]

BoldItalic, you beat me to it:
Hold the convention at your 'summer retreat', not in the middle of town. Someplace you can just set a-fire afterwards and start all over, because it's not that important to you.
Carefully screen the people you send to work out there, for loyalty and honesty and willingness to counter-snitch to you.

Be sure the 'guests' get to see your personal Palace of Versailles (because it's impressive), but tell them that you would never do any important business in the place; it's a gossip/spy heaven, and you don't want to insult your guests by having every noble in the land trying to secretly spy on them.

 

[ammulder]

Zone of Truth is highly reliable in this edition. It lasts for ten minutes, and they have to make a save once per round, with a single failure preventing them from lying for the rest of the duration. You could either trick them into standing in the area for a minute, before confessing that they have no ill intent (and don't plan on that changing for the duration of their visit), or you could make it a formal procedure for all guests to the castle.

That's very intriguing... I can't see forcing all diplomats to go through it, because come on, they all have at least SOME ill intent... And if they turn it around when you visit them, then everybody calls it quits and no diplomacy gets done.

But tricking them into it... Get one of the flunkies to carouse in a tavern with Zone of Truth and just play along until boom you suddenly ask what they're up to on behalf of their nation... That has some promise!

I'd have to think about whether that's dangerous enough that whatever standard diplomat mind shield should protect against it... But thank you, it's an excellent suggestion.

 

[Shiroiken]

The question becomes, how many are in the delegation? If it's only a few, then scrying and other divinations can be used to keep tabs on the visitors pretty effectively. If there's more, then assigning "aids" to the dignitaries who are actually spies is probably the best idea. Bonus points for assigning an elf bodyguard to the primary dignitary (who never leave's his sight) and using a Crystal Ball to constantly scry on the Bodyguard (who chooses to fail his save, or just plain sucks at it), which should get around any divination protections of said diplomat.

In general such a location should already have Arcane Locks and Alarm spells securing the most sensitive areas, such as the king's chambers, the treasury, and wherever information is kept. Posting a guard on these locations to backup the magic while the visitors are in town is probably a descent idea.

 

[Leatherhead]

Keep them intoxicated. Then send them spies disguised as personal entertainers for the dark hours, to keep an eye on them of course.

 

[Derren]

Just because they are diplomats it doesn't mean that they have to be allowed to go everywhere. There is no real reason for them to leave the castle, so don't let them.
And even inside the castle they of course are not allowed to enter sensitive areas.
And if they do have a plausible reason why they should leave the castle assign them bodyguards.

 

[MarkB]

That's very intriguing... I can't see forcing all diplomats to go through it, because come on, they all have at least SOME ill intent... And if they turn it around when you visit them, then everybody calls it quits and no diplomacy gets done.

But tricking them into it... Get one of the flunkies to carouse in a tavern with Zone of Truth and just play along until boom you suddenly ask what they're up to on behalf of their nation... That has some promise!

Tricking someone into a Zone of Truth doesn't work, because anyone who becomes subject to the Zone automatically knows that they're being compelled not to lie, and can choose to either not answer, or be misleading without actually lying. On the flipside, the caster also knows whether the subjects have succeeded on their saving throw.

Using it openly is an option, but any diplomat worth their salt would insist upon making it reciprocal. Which is fine, assuming that you are dealing with them in good faith.

Actually, it occurs to me that if Zone of Truth is an available option in a fantasy setting, it'd probably become standard practice for all official negotiations to be carried out - or at least finalised - within such a zone, or rather within two zones, one cast by each side.

 

[ammulder]

Tricking someone into a Zone of Truth doesn't work, because anyone who becomes subject to the Zone automatically knows that they're being compelled not to lie, and can choose to either not answer, or be misleading without actually lying.
...
Actually, it occurs to me that if Zone of Truth is an available option in a fantasy setting, it'd probably become standard practice for all official negotiations to be carried out - or at least finalised - within such a zone, or rather within two zones, one cast by each side.

Dang. That's what I get for reading only the first half of the spell text.

I'm not sure to what extent you'd really want to finalize all negotiations in a Zone of Truth. I sort of imagine that every side in any official agreement has ulterior motives and plans for how to subvert (strike that) "interpret" the text of the agreement in one's favor.

Though, I guess, maybe everyone would sign in a Zone of Truth, but part of the negotiation would be the exact text that must be spoken in the Zone of Truth, thereby allowing you to phrase the Zone Agreement loosely enough to hide your true intentions, just like the original agreement.

Just because they are diplomats it doesn't mean that they have to be allowed to go everywhere. There is no real reason for them to leave the castle, so don't let them.
And even inside the castle they of course are not allowed to enter sensitive areas.
And if they do have a plausible reason why they should leave the castle assign them bodyguards.

Well, what I'm more thinking is they say "thank you, now we're going to retire for the night" and enter their scrying-free quarters, leaving any guards, interpreters, personal assistants, etc. that you might have assigned them outside. Then they open a window "for fresh air" and one of them invisibly climbs/levitates to get out. Or one goes invisible and they open the door to demand fresh cake and the invisible one slips the guards. Or they just insist on going out for a night on the town to be tourists for a bit (hard to refuse -- they're not your prisoners after all). I know, for any scenario you can conceive of a counter (bar the windows, guards have See Invisible, place spies in the tavern, etc.), but the thing is they can do *anything* and you have to lay down all your counters before they have to decide what trickery they should get up to.

So all these are good ideas, but (assuming they're not dumb enough to directly attack the treasury) it still seems like the best you can do is some combination of as much spying/watching as you can get away with, and some PCs and magic-at-the-ready in case things get out of hand.

 

[Derren]

Well, what I'm more thinking is they say "thank you, now we're going to retire for the night" and enter their scrying-free quarters, leaving any guards, interpreters, personal assistants, etc. that you might have assigned them outside. Then they open a window "for fresh air" and one of them invisibly climbs/levitates to get out. Or one goes invisible and they open the door to demand fresh cake and the invisible one slips the guards. Or they just insist on going out for a night on the town to be tourists for a bit (hard to refuse -- they're not your prisoners after all). I know, for any scenario you can conceive of a counter (bar the windows, guards have See Invisible, place spies in the tavern, etc.), but the thing is they can do *anything* and you have to lay down all your counters before they have to decide what trickery they should get up to.

If they want to do that, why come into the city as diplomats at all and be noticed by the nobility and housed in the most secured building in the city instead of just coming as travellers, etc. and be totally unnoticed?
Also, in a world with magic some countermeasures should already be in place anyway.

 

[BoldItalic]

I'm wondering how you plan to embroil the PCs in all this. What level are they? And do they have any established positions in, or connections with, the court of either country? I'm guessing that your players enjoy intrigue, but what are their PC's motivations?

This will affect how much you need to define about the current situation and the plans of the two delegations. If the king has got wind of a plot by the delegates to undermine the kings' faith in his own vizier, say, there may be no need to worry about how he came by the knowledge if all the PCs are required to do is to act as the vizier's bodyguards whereas it might matter very much if the PCs are tasked with eavesdropping on the delegates and getting incriminating proof that the vizier is a double agent.