How to deal with a betrayal encounter?

[Mr.Kraken]

Here's the scene.

War. The implacable empire of Bella-Krieg is marching towards the magocracy of Pradar-Velyn. Pradar-Velyn, ruled by the Council of Six, accepts the help of the PCs to defend itself. The group has become one of the most influential names in the known world due to their power and heroic achievements and will be standing among the Council to oversee the defense of the city.

But, there's a catch. A small detail no one paid attention to. There is a tradition in Bella-Krieg that each and every person, when they come of age, should swear an oath to serve their country first and heed to its call - a tradition almost every kriegian takes pride in upholding. When the Horn of the Griffin sounds, every kriegian that plans to keep true to their oath and that has joined Pradar-Velyn in order to become a wizard will defect (or rather, return) to the Kriegian army.

With that said, one of the members of the Council of Six happens to be a secret kriegian. Predicting what would happen, he had prepared an Antimagic field as a Contingency for when the Horn is blown. The plan is for him to stand next to the Council headmaster, and when it's time to turn, the Contingency will activate, the field will go up, and he'll initiate a grapple with the headmaster and use him as a hostage to escape.

Now, GitP, that's when I need your help. Regarding readying actions outside of combat, surprise rounds and all that, how should the situation above be resolved mechanically? The Contingency/Antimagic Field combo would happen outside of combat, grappling the archmage would be his surprise action, and then normal combat begins... is that it?

[Fizban]

In order to have a surprise round there must be opponents unaware of you, where unaware means they have not detected you at all, so there is no surprise round in this situation: his target knows full well he is standing there. However, most people like this sort of setup so they allow people to take surprise rounds when "no one expected" them to attack.

A better compromise I'd say would involve a Hide or Sleight of Hand check in order to get the surprise round, if failed the target sees you make a sudden move and you have to roll for initiative.

The catch is that you're intending to wait for the contingent AMF to go off. Unless casters are unable to tell when they're in an AMF, that trigger should force everyone to roll for initiative at the same time, denying you the surprise round.

[Mr.Kraken]

In order to have a surprise round there must be opponents unaware of you, where unaware means they have not detected you at all,

I respectfully disagree with the last part. The rules says only that in order to have a surprise round, there must be opponents unaware of you. They say nothing about detecting them. In order to determine awareness, this is what the rules have to say:

"Determining awareness may call for Perception checks or other checks."

The characters are aware of the traitor, but they are not aware that he is an opponent. For them, he's another ally, and him acting against them should catch them by surprise. So, regarding the "other checks" part mentioned above, do you think the characters should roll Sense Motive or something else to notice the betrayal?

[Mordaedil]

The soldiers along the edge should maybe roll sense motive to get an "inkling" that those weapons are getting awfully close, and if they fail, they are basically too caught up in mentally preparing themselves to fight to the death infront. Only to then be caught flat-footed in a hit from the side.

I agree that they need only be aware that these are enemies to be caught by surprise.

[Quertus]

do you think the characters should roll Sense Motive or something else to notice the betrayal?

Yes, everyone should get to roll sense motive on the traitor.

Of course, most will probably think that he's up to something - like trying to remove the PCs, or making a move to become the head of the council or something.

How does the traitor even know that the horn is going to sound today?

As to how this should go down... the horn sounds, the traitor's contingent anti magic field goes off... and the head of the council disappears. Sorry, you don't make it to head of the council by holding the idiot ball. :smalltongue:

EDIT: now, if the head of the council is extra devious, he actually stays right there, and doesn't reveal that he is perfectly safe, and can still cast in anti magic, unless absolutely necessary.

[Mr.Kraken]

How does the traitor even know that the horn is going to sound today?

Because it's tradition among the army to sound the horn before it charges. And it so happens that the traitor was the Head of the Archives, the one responsible for collecting facts on history, nobility, local traditions and so on. The other members of the Council were so caught up in their own respective areas that never paid much attention to the military traditions of other nations.

[Gallowglass]

Because it's tradition among the army to sound the horn before it charges. And it so happens that the traitor was the Head of the Archives, the one responsible for collecting facts on history, nobility, local traditions and so on. The other members of the Council were so caught up in their own respective areas that never paid much attention to the military traditions of other nations.

So my question is... do the PCs know about this military tradition? Because if they haven't been informed, then they haven't (as players) had a chance to dedude what is going to happen. If so, then this encounter is going to fall flat.

DM: "A horn blasts across the battlefield and suddenly, shockingly, the Head of the Archives spurns to movement, a field of antimagic springing around him as he grabs the head of the council and holds a knife to his throat!"

Player 1: "Woah, what the hell?"

Player 2: "No way. I -told you- I was standing by the head of the council and prepared for any attack that heads his way!"

Player 3: "Why did he do that? Is the horn charming him? Did he get to make a save? I had protection from evil up. Should we be making saves?"

DM: "No, no... you see.... the enemy force have a military tradition! ...."

*several minutes of explaining OOC as the DM's smile fades slowly*

Players: "Oh. Okay... I guess should we roll initiative?"

[Mr.Kraken]

So my question is... do the PCs know about this military tradition? Because if they haven't been informed, then they haven't (as players) had a chance to dedude what is going to happen. If so, then this encounter is going to fall flat.

DM: "A horn blasts across the battlefield and suddenly, shockingly, the Head of the Archives spurns to movement, a field of antimagic springing around him as he grabs the head of the council and holds a knife to his throat!"

Player 1: "Woah, what the hell?"

Player 2: "No way. I -told you- I was standing by the head of the council and prepared for any attack that heads his way!"

Player 3: "Why did he do that? Is the horn charming him? Did he get to make a save? I had protection from evil up. Should we be making saves?"

DM: "No, no... you see.... the enemy force have a military tradition! ...."

*several minutes of explaining OOC as the DM's smile fades slowly*

Players: "Oh. Okay... I guess should we roll initiative?"

It's not a commonly known fact, but they'll have the chance to investigate it beforehand. If they don't find out, one of the council members will give out that information before the battle begins. Meanwhile, the traitor has been fooling the other members of the council all along, making them believe he came from another country. It's up to the players to suspect the council members and find out the truth. If they don't, the situation above will happen.

[Knight Magenta]

The bigger question is this: how are you planning to run the hostage situation? If all the council of 6 have more than a single level, they probably have more than about 2 hp. So how is a knife wielded by a low-strength old man supposed to be a threat?

Instead of an AMF, have the contingency contain a suitably meta-magicked fireball. Start the surprise round with another fireball + quickened fireball. Hopefully the PCs won't all be killed, but the remaining council of 5 will probably be toasty since that is who he will center the fireballs on. Once he wins initiative, the traitor would cast create undead to animate the former council members as vampires or something to prevent resurrection and then he will flee with his new minions either via flight or by teleportation.