Dragon Encounters

The last article was about strategies for lies, tricks, and betrayals. As I said then, it wouldn’t be complete without tackling the elephant in the room—the killer of all “spot the lie” scenarios—the spell called Zone of Truth.

Zone of Truth tells the caster when a creature within the spell’s area is lying. It creates massive problems for any DM trying to set up a mystery or deception scenario. There’s advice online about getting around it, but much of it is lacking. Here are my suggestions.

How to Use Zone of Truth Without Killing the Game

The Main Principle: Use Something the Players Haven’t Considered

The main way to get past the spell is to say something technically true—true enough not to trigger the magic—while leading the players to interpret it differently. Plenty of fantasy books circumvent truth-detection effects the same way.

The problem is that writers don’t face live players who will cross-examine them. Players ask questions you aren’t prepared for. They notice when you spend a long moment choosing your exact words. Then they jump on your careful answer with a dozen more questions—or insist the NPC repeat a specific phrase.

There are several ways to pass an answer past the players’ radar. What they share is that you need to have a factor up your sleeve that the players haven’t even thought of.

Examples

Example 1: Protecting a Secret Goal from the Villain

Set-up. The players want to keep their goal secret from a villain—either so the villain can’t prepare countermeasures or can’t ambush them. They cast Zone of Truth and bind a priestess to oaths: she won’t tell anyone what they share with her, won’t write it down or stash it somewhere it might be found, and won’t let any follower who overhears reveal it either.

Obvious dodge—and why it fails. She “plays twenty questions” with the villain until he puzzles it out, or she drops breadcrumbs he can follow. This is something the players might foresee, so assume they close that loophole in the oath.

Better dodge. There are mind flayers in the area—friendly to, or employed by, the villain. The priestess arranges for one of her followers to fall into their hands after learning the secret. The follower isn’t revealing the information, and the priestess isn’t placing it where it can be discovered. The priestess merely sends the follower to where the mind flayers can extract it. (Ideally, she’ll set it up so that they players tell him the secret. Once they have her on their side, they’re unlikely to worry about her minions.)

This only works if the players haven’t thought of mind flayers. You can foreshadow illithids before the priestess slips the secret—that’s recommended to keep things fair—but if the players already know about mind flayers at the time of questioning, they’ll likely cover this in the oath.

Example 2: The McGuffin vs. the Power Source

Set-up. The players seek a magic-item McGuffin needed to save the day. Inside Zone of Truth, the priestess says she has no interest in the item, won’t take it from them, and only wants to ensure a certain someone else can’t have it. (Give her a motive for helping.)

Rejected plan. Maybe she intends to destroy the item—causing a chain reaction, an explosion that kills the party, or simply rendering the item unusable so nobody can have it. This won’t work. Players will force her to spell out everything she thinks about the item and her plans for it. “No interest in possessing the item” will trigger intense follow-ups.

Better plan. She truly doesn’t care about the item. She wants its power source—a battery, “power crystal,” or similar—because it can fuel or trigger something else. She can honestly claim no interest in the item itself.

Fair play note. For this to work, the players shouldn’t already know that you can extract power from an item. To keep it fair, let them learn that after questioning the priestess but before the betrayal—perhaps they must do a side quest to “recharge” the McGuffin, or they extract energy from something else along the way.

Practical Rules for Using Zone of Truth at the Table

Let Them Cast It—But Make It Cost Something

If the players ask to question the priestess under Zone of Truth, let them. If she refuses on principle, they’ll never trust her again.

She can still be offended and demand compensation: a short quest, a favor with long-term consequences (someone now wants revenge; an ally distrusts them by association), or a quid-pro-quo interrogation where they must also answer her questions. Pair this with something they don’t want to reveal—perhaps a secret they were told to keep, an admission that would make her initially refuse to work with them (until later), a higher price, or a confession about treasure she has a claim to.

This will make them less likely to question her under Zone of Truth a second time, and set the stage for her refusing if they want to.

When Their Question Breaks Your Plan

If they ask something that would make your betrayal impossible, and it’s reasonable that she would agree were she not planning a betrayal, have her agree. Maybe you’ll find another angle later; if not, it’s still to her benefit not to be branded an enemy—and to yours, because they’ll distrust the next villain a little less. Don’t agree to a bargain that only makes sense if it enables a betrayal; it will look suspicious, and she must plan for the worst case where the betrayal fails.

If She’s Caught

If she’s trapped by a question about the past that she can’t answer without incriminating herself, let her remain calm and unapologetic. She can say, “Of course I had contingency plans—anyone worth working with can defend themselves,” or, “I’m sure you would betray me too, given the chance and the imagination.”

What you don’t want is cartoon villainy—outrage, empty threats, or childish bluster. That robs the character of dignity. (“Oooh, you twicked me, you wicket wabbit”)

Common Oath Wordings—and Their Catches

These lines are likely to slip past player notice, though nothing is guaranteed. A careful NPC will guard her interactions before the interrogation in anticipation of Zone of Truth.

• “I will not lie to you about any dangers that might kill you.”
  This lets her omit details so long as every statement she makes is factual.

  • “I” allows a minion to deliver news and lie about it.

  • “You” could be argued to let her lie to one PC while addressing another. That’s messy at the table; use with caution.

  • “Dangers that might kill you” permits lies if the plan is only to capture them, or to steal items and undermine them without lethal intent.

• “I will tell you of any significant dangers I know of that my advice might cause.”
  A promise not to let them stumble by omission—on paper.

  • “Significant” may exclude multiple small threats that add up to real peril.

  • “I know of” can mean “know now,” not “discover later.”

  • “Know” excludes suspicions.

  • “Tell you” doesn’t require clarity: she can bury the warning among minor notes, or make a major threat sound minor.

• Nasty but legal twist: Warn of “a dangerous water monster,” knowing there’s a lesser one that fits the description. When they beat the lesser threat, they’ll assume the danger has passed—then the greater one strikes.

• Telling ≠ telling truth about everything.
  She can truthfully warn of a danger while also giving them a “solution” that doesn’t work—worsening their position when they try it.

• What counts as “telling”?
  Can she “tell them” during combat, or while they’re near a waterfall where they literally can’t hear? Pedantic—but in a tight oath, pedantry matters.

The “Master of Emotions” Escape Hatch (And Why Not to Use It)

In theory, a disciplined spellcaster could lie under Zone of Truth by self-deception. The spell only blocks lies the speaker knows are lies. In many fantasy worlds, casters master visualization techniques as part of learning magic. These could be used to make oneself temporarily believe falsehoods or to make a decision whole heartedly even though they know they will later rescind it.

I would not use this at the table: your players will cry foul, and they’ll be right. It exceeds reasonable expectations of the spell.

Why mention it? Because sometimes a long campaign produces contradictions that only surface sessions later. If you realize immediately, adjust the scene. If you notice much later, you’re stuck—usually you apologize and everyone pretends the slip never happened. “Master of Emotions” offers an in-world patch to be used only when you have already owned the mistake out of character. It’s a last-resort continuity fix, not a normal tactic.

Avoiding Zone of Truth Entirely

The best defense is never giving the players a chance to cast it.

• Don’t meet in person. Use written messages, intermediaries with memorized lines, or magical “phones” like message and similar effects.

• Show up when it’s unavailable. Use divinations to learn when they don’t have Zone of Truth prepared, or when they’re out of slots.

• Exploit timing. Appear in the middle of a combat or crisis, then end it by sending them one way while you dash another, or by creating urgency that prevents interrogation.

• Use an impersonator. A loyal drow mage with alter self can stand in, or any similar method. Ensure the double keeps to promises already made. Reveal the existence of the impersonator later—not earlier—or they’ll check for it on the spot.

Of course, this only helps solve one problem. Sometimes, your villain is so evil that it doesn’t seem like your players would even listen, no mattter what. See Glabrezu for a few solutions.

Using Zone of Truth in Mysteries

Many DMs worry that Zone of Truth ruins mysteries. The solutions aren’t so different from the above.

• Block the obvious question. “Did you do it?” is predictable. Have the culprit use intermediaries or set things in motion to happen on their own.

• Design around common questions. If you’ve run mysteries before, you know what they’ll ask—structure your scenario so the easy questions aren’t decisive.

• Shared responsibility. If they ask, “Are you responsible?” make the answer “partly” true for multiple parties. One NPC can admit to a trifling role that sounds like the whole story—while the deeper guilt lies elsewhere.

• Leverage uncertainty. Poisoning where you don’t know whether the victim swallowed it; abandoning someone in a likely-fatal situation—all allow “I don’t know” to be literally true. (Finally, a reason for those elaborate villain set-ups where the hero might escape.)

• “I can’t say.” Works if there’s a magical oath or similar truth-binding reason. Failing that, “I’d rather not answer. I can’t be sure,” rides the uncertainty you’ve baked in.

• Misdirection the players can discover. Make it look like fire when it was really poison, a knife wound, or drowning. This buys you slack while remaining fair: they could still deduce it.

• Have a backup objective. If they catch the villain early, ensure they still need the motive, the treasure’s location, or an accomplice.

• Apply time pressure. They only get limited Zone of Truth uses per day. Put them on a clock so they must spend slots elsewhere too—this often makes adventures better anyway.

• Give other suspects reasons to hold back.

  • Lesser crimes (e.g., theft) they fear will come to light.

  • Guilt or fear that something they said or failed to do contributed to the death.

  • Fear of retaliation if they admit what they suspect.

  • Partial complicity under duress.

• If and only if you’ve warned them that disciplined liars might resist Zone of Truth, you can use the “Master of Emotions” option in mysteries—but again, reserve it for rare cases and keep it sign-posted.

• Or just keep NPCs unavailable. A classic that still works: the key witness is missing, the culprit escapes, or the courier is dead.

For tactics for making spells more effective, see Monster Combat Tactics