In the DMG for 5th ed there is established DC levels for how NPC's will respond to you in social interactions based on whether they are friendly, indifferent, or hostile to you as detailed in the Conversations Reactions Table on pg 255 of the DMG.
DC Friendly Creature’s Reaction
0 The creature does as asked without taking risks or making sacrifices.
10 The creature accepts a minor risk or sacrifice to do as asked.
20 The creature accepts a significant risk or sacrifice to do as asked.
DC Indifferent Creature’s Reaction
0 The creature offers no help but does no harm.
10 The creature does as asked as long as no risks or sacrifices are involved.
20 The creature accepts a minor risk or sacrifice to do as asked.
DC Hostile Creature’s Reaction
0 The creature opposes the adventurers’ actions and might take risks to do >so.
10 The creature offers no help but does no harm.
20 The creature does as asked as long as no risks or sacrifices are involved.
These levels of familiarity seem to be more geared towards determining the DCs for persuasion checks more than they are for determining the DCs for Intimidation checks. This perception is reinforced by the common practice that a failed intimidation check can result in a persuasion check no longer being capable (a DM's interpretation I know, and not one I agree with, but one I have seen at more than one table).
To help in explaining here are the descriptions of the three levels
A Friendly creature wants to help the adventurers and wishes for them to succeed. For tasks or actions that require no particular risk, effort, or cost, friendly creatures usually help without question. If an element of personal risk is involved, a successful charisma check might be required to convince a friendly creature to take that risk.
An Indifferent creature might help or hinder the party, depending on what the creature sees as most beneficial. A creature’s indifference doesn’t necessarily make it standoffish or disinterested. Indifferent creatures might be polite and genial, surly and irritable, or anything in between. A successful Charisma check is necessary when the adventurers try to persuade an indifferent creature to do something.
A Hostile creature opposes the adventurers and their goals but doesn’t necessarily attack them on sight. For example, a condescending noble might wish to see a group of upstart adventurers fail so as to keep them from becoming rivals for the king’s attention, thwarting them with slander and scheming rather than direct threats and violence. The adventurers need to succeed on one or more challenging Charisma checks to convince a hostile creature to do anything on their behalf. That said, a hostile creature might be so ill-disposed toward the party that no Charisma check can improve its attitude, in which case any attempt to sway it through diplomacy fails automatically.
Given this description for the levels, I am going to try to detail a few points of confusion.
This is supposed to be for all charisma checks but the easiest to accomplish is when they are friendly. Why would a character intimidate or threaten someone who is friendly to them, and wouldn't that make them no longer friendly, and therefore make it harder?
The description for Hostile specifically mentions the word diplomacy in lieu of charisma check, which is not a term I would use to describe intimidation most of the time and lends better to the idea of being persuasive.
The description for hostile also indicates that there is a point where a character can become so hostile that no amount of charisma checks could persuade them, however, why would them being hostile prevent them from being subject to intimidation?
There does not seem to be a rules clarification that could help deal with the issue of how to deal with intimidation checks other than using a system that does not adequately represent them. In this absence, I am seeking judgment from a practiced GM on whether one of two alternatives I have come up with constitute a consistent way for creating DCs for intimidation checks? I am also interested in hearing any alternative ways of dealing with this situation that other GMs have found work.
Possible Solution 1:
Would it be reasonable to add two more levels to the Conversation Reaction Table with hostile being the center and having persuasion and intimidation work best on opposing sides of the list so that it looks something like:
Possible Solution 2:
Or would it be better to create a separate reaction chart to allow for a character to feel threatened and friendly at the same time as is sometimes possible in reality so that you would have two charts that parallel one another like so:
Possible Solution 3:
Or are both of these adjustments too cumbersome to work properly and is there a better way to handle this?