Diplomacy

The following is taken http://www.giantitp.com/forums/showsinglepost.php?p=9606632&postcount=2 and adjusted for ranks in Diplomacy not being able to outrank your level. This means that Diplomacy is capped at 6 before Class Skill, the Great Negotiator feat, and Charisma Modifier is factored in, which brings its maximum possible total to 15. Use Diplomacy (Cha) to ask the local baron for assistance, to convince a band of thugs not to attack you, or to talk your way into someplace you aren't supposed to be.

Check: You can propose a trade or agreement to another creature with your words; a Diplomacy check can then persuade them that accepting it is a good idea. Either side of the deal may involve physical goods, money, services, promises, or abstract concepts like "satisfaction." The DC for the Diplomacy check is based on three factors: who the target is, the relationship between the target and the character making the check, and the risk vs. reward factor of the deal proposed.
 * The Target: The base DC for any Diplomacy check is equal to 10 + level of the highest-level character in the group that you are trying to influence + the Wisdom modifier of the character in the group with the highest Wisdom. High-level characters are more committed to their views and are less likely to be swayed; high Wisdom characters are more likely to perceive the speaker's real motives and aims. By applying the highest modifiers in any group, a powerful king (for example) might gain benefit from a very wise advisor who listens in court and counsels him accordingly. For this purpose, a number of characters is only a "group" if they are committed to all following the same course of action. Either one NPC is in charge, or they agree to act by consensus. If each member is going to make up their mind on their own, roll separate Diplomacy checks against each.
 * The Relationship: Whether they love, hate, or have never met each other, the relationship between two people always influences any request.


 * -8 Intimate: Someone who with whom you have an implicit trust. Example: A lover or spouse.
 * -6 Friend: Someone with whom you have a regularly positive personal relationship. Example: A long-time buddy or a sibling.
 * -4 Ally: Someone on the same team, but with whom you have no personal relationship. Example: A cleric of the same religion or a knight serving the same king.
 * -2 Acquaintance (Positive): Someone you have met several times with no particularly negative experiences. Example: The blacksmith that buys your looted equipment regularly.
 * +0 Just Met: No relationship whatsoever. Example: A guard at a castle or a traveler on a road.
 * +2 Acquaintance (Negative): Someone you have met several times with no particularly positive experiences. Example: A town guard that has arrested you for drunkenness once or twice.
 * +4 Enemy: Someone on an opposed team, with whom you have no personal relationship. Example: A cleric of a philosophically-opposed religion or an orc bandit who is robbing you.
 * +6 Personal Foe: Someone with whom you have a regularly antagonistic personal relationship. Example: An evil warlord whom you are attempting to thwart, or a bounty hunter who is tracking you down for your crimes.
 * +8 Nemesis: Someone who has sworn to do you, personally, harm. Example: The brother of a man you murdered in cold blood.
 * Risk vs. Reward Judgement: The amount of personal benefit must always be weighed against the potential risks for any deal proposed. It is important to remember to consider this adjustment from the point of view of the NPC themselves and what they might value; while 10 gp might be chump change to an adventurer, it may represent several months' earnings for a poor farmer. Likewise, a heroic paladin is unlikely to be persuaded from his tenets for any amount of gold, though he might be convinced that a greater good is served by the proposed deal. When dealing with multiple people at once, always consider the benefits to the person who is in clear command, if any hierarchy exists within the group.


 * -8 Fantastic: The reward for accepting the deal is very worthwhile, and the risk is either acceptable or extremely unlikely. The best-case scenario is a virtual guarantee. Example: An offer to pay a lot of gold for something of no value to the subject, such as information that is not a secret.
 * -4 Favorable: The reward is good, and the risk is tolerable. If all goes according to plan, the deal will end up benefiting the subject. Example: A request to aid the party in battle against a weak goblin tribe in return for a cut of the money and first pick of the magic items.
 * +0 Even: The reward and risk are more or less even, or the deal involves neither reward nor risk. Example: A request for directions to someplace that is not a secret.
 * +4 Unfavorable: The reward is not enough compared to the risk involved; even if all goes according to plan, chances are it will end up badly for the subject. Example: A request to free a prisoner the subject is guarding (for which he or she will probably be fired) in return for a small amount of money.
 * +8 Horrible: There is no conceivable way the proposed plan could end up with the subject ahead, or the worst-case scenario is guaranteed to occur. Example: A offer to trade a bit of dirty string for a castle.
 * Success or Failure: If the Diplomacy check beats the DC, the subject accepts the proposal, with no changes or with minor (mostly idiosyncratic) changes. If the check fails by 5 or less, the subject does not accept the deal but may, at the DM's option, present a counter-offer that would push the deal up one place on the risk-vs.-reward list. For example, a counter-offer might make an Even deal Favorable for the subject. The character who made the Diplomacy check can simply accept the counter-offer, if they choose; no further check will be required. If the check fails by 10 or more, the Diplomacy is over; the subject will entertain no further deals, and may become hostile or take other steps to end the conversation.
 * Action: Making a request or proposing a deal generally requires at least 1 full minute. In many situations, this time requirement may greatly increase.
 * Try Again: If you alter the parameters of the deal you are proposing, you may try to convince the subject that this new deal is even better than the last one. This is essentially how people haggle. As long as you never roll 10 or less than the DC on your Diplomacy check, you can continue to offer deals.

Living with the Rule
Note that while this example uses the traditional law/chaotic and good/evil alignment chart, the Valoria campagin does not use them. Valoria is founded upon ideologies and motivations--after all, sometimes "lawful good" actions can still conflict greatly.
 * A 5th level party is trying to get into an extravagant ball being thrown by a local baron (who is secretly an evil cultist). The party bard, with a Diplomacy of +13, tries to talk his way in. Three guards at the door are only letting in those who are on The List. Their captain is a 5th level fighter, and they are accompanied by a 1st level aristocrat with a Wisdom of 13, giving a base DC of 21 (the remaining guards are lower level and have Wisdoms of 10, so they don't add to the DC.) The guards have never met the adventurers before, so the Relationship modifier is +0. The final DC, however, depends on how the bard chooses to try to talk their way past the guards:
 * If the party approaches the guards and simply asks to be let in, they are offering a risk of "failing in your duty and probably getting fired or reprimanded" against a reward of "nothing". The guards might not get caught, but don't really get anything out of the deal either; it's an Unfavorable deal and gets a +5 increase to the DC, for a total of 26. The bard needs to roll a 13 or higher; not impossible, but risky.
 * If the party slips a pouch with 20 platinum pieces into the hand of the guard captain first, though, the deal becomes more favorable. Since even split four ways, the platinum is a decent amount of money compared to how much they get paid. Sure, they might get fired, but the platinum could keep them well-fed until they found another job anyway. The deal is now Favorable, and gets a -5 decrease to the DC, for a total of 16. The bard needs to roll a 3 or better-pretty easy.
 * If the party dresses up as aristocrats and successfully Bluffs the guards into believing they are nobles, the deal alters as well. The guard may get fired for letting in someone who is not on The List, but then, this noble before him may get him fired for keeping them out of the season's social event. Either way, the guard might lose his job, so the deal is Even, and the DC stays at 21. Our bard needs to now roll an 8 or better to succeed.
 * If, unbeknownst to the bard, the guard captain is fully aware of the evil baron's cult activities, things change again. First, the baron may have threatened the captain with a painful death if he fails his duty; thus, whatever method the bard uses to approach the guard will be one step less favorable, since the worst-case scenario is a brutal death rather than just job termination. The risk is much higher than the captain lets on, so if they offer him nothing in return the deal is Horrible for him, increasing the DC by +10 for a total of 31; the bard needs to roll an 18 or better-very unlikely. Further, if the captain is in on the baron's evil dealings and recognizes the adventurers as agents of Good, he might be considered an Enemy and qualify for an additional +5 increase to the DC based on relationship, for a total of 36! This is a recipe for disaster if the bard attempts it, but he doesn't know that.
 * But then again, if they discover that guard is Lawful Good, the bard can suggest that they are there to take expose the baron's dirty deeds. The bard is still offering no money, but now the "payment" is the action the adventurers will take that supports and exemplifies the guard's alignment. The deal is Favorable for him once again, since even if he is fired, he will have the satisfaction of knowing he helped thwart an evil plan. If the bard also slips the captain 20 platinum, it might push the deal up to Fantastic, for a grand total DC of 11. The bard then needs a -2: he will automatically succeed, though of course he doesn't know that either.
 * Finally, let's say the bard offers a bribe, but it is only 50 gold pieces. That's not enough to split 4 ways and live off if they get fired, but it is decent-an Even deal, DC 21, and the bard needs an 8 on the die. But whoops! He rolls a 5! That's within 5 of the DC, though, so the captain looks at the gold and replies that this is only enough for one of them, and that he needs another 50 gp for his three friends. He's giving the bard the parameters of what would make the deal Favorable to him-200 gp, as in the first example. The bard can either pony up the extra 150 and end the conversation now, or he can try a completely different tack and roll again.

Options and Ideas:
At first read, it may seem like a pain to remember the two modifiers. There are tow things that make it easier, though. First, in most games, 90% of all Diplomacy checks will be against total strangers, which is a +0 Relationship modifier. If there's no established relationship, there's no Relationship modifier. Second, notice that both modifiers have the same set-up: +10 to -10. That's intentional; even if you can't remember what modifier is appropriate, you can easily "wing it" by just remembering the upper and lower limit allowable, and judging accordingly.

The new Diplomacy skill offers a built-in definition for the sometimes-difficult-to-adjudicate charm person spell: a charmed creature is treated as having a Friendly relationship to the caster (-7 to Diplomacy DC), which replaces any previous relationship modifier. Thus, by charming an enemy, the DC drops from +5 to -7, a decrease of 12. The caster can now talk the creature into anything this improved relationship allows, without every NPC being wrapped around the caster's finger because of a 1st level spell. Note, however, that this will make the spell far more useful to a bard, who has Diplomacy as a class skill and has a high Charisma, than to a wizard. You might like that-maybe the bard should be better at charming people-but if not, I suggest allowing the caster of charm person to use his or her caster level in place of their Diplomacy skill check for that creature only. Thus, the DC is still affected by the Risk/Reward modifier and the (newly improved) Relationship modifier, but the check is either a Diplomacy check or a straight caster level check.

Sometimes, you may not have a good appreciation of what might be a good deal to offer. You can use Knowledge checks or even the Appraise skill to determine what a "fair trade" might be. Divination spells might play a part as well; a well-timed augury or even a detect good spell can give you a decent idea of what a particular NPC might find valuable.

Resist the urge to throw in lots of circumstance modifiers. The point of this system is to incorporate the NPC's overall evaluation of the situation into one number, so avoid giving modifiers like "+2 because they are wary." That should already be covered when they ponder the Risk vs. Reward factor and when their Wisdom modifier is applied to the DC. You might consider a modifier in a situation where the physical situation makes Diplomacy more difficult, such as shouting across a bridge, or having your words relayed through a third party, but try not to "double-dip" for situations for which the system already accounts.

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