Sure, you can agree to anything. If you didn't think it through and thus suffer from skill issues. And there are of course good stories to tell with it, like in this secret traitor situation, and good players will apply circumstantial bonuses fairly. Doesn't mean you shouldn't be aware that another player can't force you into simple contested rolls on the nature of reality.

I mean, that's why in any such contested roll between PCs you should have both parties agree to the roll and just see how the dice land? And if they don't agree to it, they're free to roleplay it how they wish to. That's how we do it at least. I don't see why you have to call someone's preference on how to play a "skill issue" though.

In what edition of the rules, for what system, and what page number of that rulebook would I find your version of these rules in?

Wouldn't that be metagaming? I know general game mechanics pretty well to perceive many things a character would not know. I am pretty sure that in the spirit of roleplay i have to adjust to my characters Stats. In the example it would be Elon rolling their deception against my intelligence/perception, which whatever skill the Dm decides is most relevant. Also because the game Master is always right and has the final say as an actual dictator. The player abuse and sex stuff just seems like a consent issue. There are probably groups that are into that just like there are many that don’t. A good Dm and play group should communicate beforehand if they allow such things and also respect peoples wish to stop playing if they are uncomfortable. They can also use the [x-card](https://docs.google.com/document/d/1SB0jsx34bWHZWbnNIVVuMjhDkrdFGo1_hSC2BWPlI3A/mobilebasic) system

Perhaps I'm wrong, but from their response and seeing this situation happen so often it sure doesn't seem like the players are aware that all skill checks have inherently circumstantial difficulties. Simple roll vs roll contests just tend to be the default of players that haven't read the rules for these circumstances, something about the way the game is set up just doesn't clue players into that fact. Maybe it's just that players simply aren't primed to accept that they can set their own DC bonus and it's not even metagaming? It's basically the only circumstance that they can. It's probably a good DM habit to get into, come to think. "What's your character's willingness to believe this" type prompting.

Those circumstancial bonuses or penalties are given by the DM. If the DM doesn't inform the players what they are for the current situation, thats the fault of the DM, not the players.

I had to play my own evil doppelganger in my DM's campaign. My character got kidnapped and got replaced by a copy, which was there to spy on the party (the DM only gave me enough info to work with at the beginning). I was given some powers which my character didn't have and started to abuse them. The DM specifically allowed for infinite uses of "Detect Thoughts" (lvl 2 spell, which I only had three uses at level 6), which I put to maximum use, on every NPC encounter the party had. It seemed that none of the other players noticed, so I started putting on more chaos and evil in "chaotic evil doppelganger". I started having them act in a more sadistic and erratic manner, but still no effect. I started asking other players (out of the game) what if there were an impostor in the party, but not much response. The only halfway decent response I got is a "who cares, if they're helping the party, it shouldn't matter." I gave up at that point. My character, and the one the doppelganger is a copy of, is the party healer. I got used to playing him normally (me, the player handling the doppelganger as if it were the original, just with more powers, and a slight personality alteration) until the DM informed me that it's time to pull off the reveal. I was caught by surprise, but I knew I had to do my part. After what was supposed to be the boss battle, the DM gave me the signal and I said "It's been fun, guys, it really was, but unfortunately..." The rest of the party was alarmed, and the DM had me fight the party, with monsters coming to my aid. Now, the party's out of a healer, and had to fight a horde of monsters. Some of the other player characters (based on their characterization) were reluctant to fight my doppleganger, but I tried my best to goad them into fighting. My character isn't the best fighter, but I did an effort. I knew the party's weakest link (my original character) but also, how the glass cannons worked. So I started directing the monsters to target them first. It was a close fight, but teetering on a TPK. The DM then introduced my original character (controlled by the DM temporarily) who swopped in to save the day. There were lots of swearing after the DM ended the session that day.

The DM sets the mental circumstances for his characters and you set yours. Your character is not summed in its entirety by their skill bonuses, and the DM by definition does not know your character better than the person playing them. That character, like any other person, can refuse to believe something they don't want to believe, for whatever reason makes sense to them. For example, they could ignore someone telling them an objective truth they could *easily* verify themselves by reading the relevant portion of the DMG.

I still would like to know what relevant portion of the DMG you are referring. I know of no such table for any kind of "mental circumstances" or anything close to what you're describing. It sounds like homebrew stuff or confusion with some rules regarding psyonic abilities.

The big problem with twists like these... If you know they're coming, it sort of ruins the surprise. If the GM asks if it's okay to have party betrayal (or if someone else asks and the GM says yes) then you're constantly on the lookout for it - because why would they ask if it was irrelevant? Of course, nothing says the GM can't ask an irrelevant question in the same manner they keep irrelevant minis next to their screen, but it's something that's usually frowned upon (what amounts to non-consensual PVP), so if it's known to be ok, you'll be looking out for it and then the twist won't stick. Of course, if you *don't* know it's coming, then it's never a place your brain will go. You aren't just going to accuse a character (and thus player) of working against the party because that's a heavy accusation. It carries a lot of weight behind it since you're only a few steps down from calling someone a problem player. Players often don't have a good enough grasp on other players' characters to notice behavioral shifts, and players often don't have good enough acting skills to roleplay them correctly. I've yet to hear a story where someone figured this kind of twist out before the reveal, and that doesn't surprise me at all.

The multiple sections where it says the DM *doesn't control the PCs* and describes the mechanics and *reasons* to roll skill checks in the first place. Having a section describing how to do a contested roll isn't the same thing as saying that is how you handle all player vs player skill checks, and it assumes you know that circumstances should affect the rolls beyond the numbers on your character sheet. Tbf 5.0 was actually pretty bad about splitting up this information between the PHB and DMG.

The DM *isn't* controlling the players. The player of the paladin is choosing to use sense motive against my bluff checks. Again, any circumstancial penalties or bonuses that are not inherent on your sheet are typically given by the DM. Such as you entering a room that has some kind of field or obstacle that imposes a penalty or confers a buff. It does not mean that a player can say "I have a super high iron will and so I get a +40 to any mind affecting spells!"

Not what I'm saying, and I know you don't understand the problem, because you're talking about spell save DCs which *are not skill checks and are specifically under DM purview as a magical mind altering effect.* Think of it like this: You have the right, as a player, to decide your character fucking hates someone so much they will not believe a word they say under any circumstance. It could be you're metagaming, but that's a separate problem beyond the scope of skill, ability, and spell save checks.

Holy shit. No. I am not talking about spell save DCs; I am talking about circumstances that would provide a bonus or penalty that might not appear on your character sheet, using magical effects as an example.

Yes, you are, and you don't know enough to know what you just said.

Let's use a different example then. The characters have entered a room where the wind is absolutely howling, affecting their hearing, movement and balance. Anything they do in that room that requires a listen, movement or a balance check, has a -5 penalty. That is a circumstancial penalty.

Sure. And *you as the player* are the one who decides *what the metaphorical wind is like* for your character's *attitude towards the people and world around them.* Don't trust the king? Good news, you can tell the DM that, and they can't say "yes you do" unless you are affected by magic. They also can't roll the king's Persuasion to change your character's mind about that *without you agreeing to how the DC is set, including potentially a straight contested roll.* Or, to put it another way: Just because they didn't find a trap in the hallway doesn't mean they *have* to think there isn't one, especially if there's a posted sign saying "This hallway is trapped."

There is a difference between "you believe what they say" and "you can't tell if they are lying." The sense motive roll's outcome only says whether or not they can tell if another character is lying; not even what the lie *is* or have anything to affect their personal belief. He might *know* the cleric is a bad guy; *he just can't prove it.*

You could privately talk to your GM and say your character wants to cover all of their bases, so just like batman, spends time strategizing about how to defeat the other party members and making preparations in case they betray the group or him. Like a ring of concentration that also has an anti-magic curse activated when the correct word is spoken in its vicinity for the mage, secretly planted on the body of a mob that your character manages to get to before the party loots. And then, of course, you're in a position where you could betray the party and surprise even the GM. Though a counter argument to what you're saying is that deception games are a thing and the players knowing that there are enemies in the group doesn't make those games trivial to figure out. A deception RPG could be interesting to play.

And he can think whatever the fuck he wants about that, which is entirely my point, because *he, as a theoretically sentient being, is aware that he is flawed.* Unless there's a character driven reason not to! Arrogance, naivete, backstory, whatever. But, more pressingly, my point is to make *you* aware that there are more options available to the system for Deception checks than pure statblock measuring! And every table should be aware of that! Which I'm still not convinced you are, because this argument is still going.