On the one hand, usual formulation is you only get one question, finding out which is the liar alone is easy but useless as then you’re out of questions to actually get through the gate. On the other hand, unless you get the information about the behavior of the guards from a trusted source that isn’t them you have no reason to believe them, and in fact they cannot relay the setup to you accurately without giving it away if you assume they’re always like that as many do.
Sadistic DM Take - Both guards are liars and they came up with this rouse to fuck with people because they were bored.
Necro raises first guard, compels him to kill second guard.
Necro raises second guard, has them each explore the path they blocked to check for danger
Both guards told the truth in their first lines
Not if they were both lying. Both guards are liars.
Barbarian street smarts ain’t by the book (or all that smart), but damn are they effective
Guard 2 says: “The other one nothing but lies”, which is assumed to be true. From the guard that lies. Was that a lie?
Well you should assume that both guards follow the rules all time. Meaning that the initial setup of the rules cannot be trusted, because who knows if the talking Guard is lieing or not. If one does tell nothing but the truth this must be the one explaining the rules.
However if I remember correctly it was setup that one will answer the truth while the other one will deceive me. Meaning he might tell the truth if it confused me.
So no question might work.
Simple logic twisting really. Ask any guard what other guard would say, negate that answer and you got the right answer.
How though?
A truth B lies
Ask A: answer is No (truth)
Ask B: answers is No (lies)
Let’s suppose A always lies and B always tells the truth.
You ask A what B would say this being a correct path. In this case B can’t lie and will tell True, A will then lie about that and will say False, you negate False -> True.
Say you ask B what A would say this being a correct path. In this case A always lies and if road is correct they will say False, B who can’t lie will tell you A would say False, you negate that -> True.
I’ve always found it easier to just ask the question within the question. To either guard.
“If I were to ask you, ‘which path is safe?’, what would you say?”
If you asked the truth teller he will Indicate the correct path because he would have told you the correct path anyway. If you ask the liar he originally would have indicated the bad path- but now he has to lie about what he would have original told you and will now indicate the safe path. Asking what the other guard would have said just kind of adds another unnecessary logic wrinkle in my mind.
This assumes A can only lie. But I guess that is the riddl.
