Two of my players' characters have been replaced by doppelgangers who want to steal money from adventurers (while letting them get into most of the danger), with the eventual object of escaping with the funds to set up a fraudulent merchant business. The players are aware that they are now playing doppelgangers, and happy to go along with it.

Doppelgangers usually try to isolate party members before killing them, and, in this case, taking their gold. The problem is that all action is usually narrated by the DM. A possible solution is that I narrate some pre-agreed encounter, which is almost guaranteed to kill the target, but which is not, in fact, happening, and which can then be reported back to the party by the doppelganger as the reason for the unlucky character's demise.

In another ploy, the doppelgangers may wish to strip treasure from undiscovered rooms before the rest of the party get there. Once again, I have to know not to narrate the discovered treasure, but somehow tell the doppelgangers what they have actually found.

The players may also come up with other schemes that require coordination between us, or between themselves, without the other players knowing. Passing the notes telling them of the change has already aroused quite considerable suspicion, so this is not a workable solution.

Ideas we have already thought of include:

  • Pre-agreed code words or phrases which trigger particular events (these could be difficult to remember in practice).

  • Sending each other messages on our phones during breaks (does not allow communication during the session).

How else can the two doppelganger players and I coordinate the deception?

  • 1
    \$\begingroup\$ A related question on betrayal/deception between players that never got too much attention sadly: How to prevent metagame in betrayal/PvP scenarios? \$\endgroup\$
    – HellSaint
    Aug 3, 2018 at 21:30
  • 1
    \$\begingroup\$ The core of both questions, imo, is how the DM can coordinate with the betraying player(s) without giving that information to the other players. \$\endgroup\$
    – HellSaint
    Aug 3, 2018 at 21:31
  • 2
    \$\begingroup\$ Super relevant: How to secretly talk to one of the players while DM'ing? \$\endgroup\$ Aug 3, 2018 at 21:48
  • \$\begingroup\$ @HellSaint That's quite a similar problem, excepting only that mine is even more difficult, since I have two players betraying the party. The first answer (keep passing notes around) may be useful. The second (social contract not to metagame) doesn't really help unfortunately, as we play a difficult survival game in which the players really have to use everything they have just to stay alive. I've therefore never made any distinction between player and character knowledge. I agree that the question could definitely do with more attention. \$\endgroup\$
    – Ladifas
    Aug 3, 2018 at 22:48
  • \$\begingroup\$ @DanielZastoupil Thank you for that. That is even more useful than HellSaint's question and has given me a variety of ideas (largely boiling down to: if you're going to communicate with one player in some way, then do the same with the other players, but with irrelevant or other information). Unfortunately, it doesn't really deal with how the players can secretly communicate at the table, nor how they might take advantage of more emergent opportunities which we couldn't plan for in advance. \$\endgroup\$
    – Ladifas
    Aug 3, 2018 at 22:50

2 Answers 2


Take inspiration from real-world spies.

Your doppelgangers are essentially operating undercover and attempting to communicate without being intercepted or spotted by other members of the group they've infiltrated. Why re-invent the wheel when Cold War era spies conducted similar activities for decades?

Real-world spies could often not communicate with each other freely; they had to arrange meetings, or dead drops of information and items, and might go for long periods of time without actually interacting with each other. They might not have reliable methods of communication. Players acting as spies should expect that they may have to do the same.

In private messages, task your doppelgangers with the responsibility of finding their own methods and opportunities to communicate without being overheard or understood. This creates an interesting challenge for the players and rewards them for clever gameplay. Their real-world equivalents often had to think on their feet.

The players can leave messages for each other hidden in a pre-arranged place in the bathroom.

During the game, the players can signal the DM or each other by certain things which normally appear innocent:

  • Using certain dice. For example, the player might keep a specific red d20 aside when not using it; they only use this to signal something to the DM (e.g. when they are rolling a Survival check to make a trail, but are secretly leaving chalk marks to allow the group to be followed). This is tricky because it relies on the DM noticing; putting the special dice away when not using it would make it slightly more clear.
  • The players might use a certain spell only in certain circumstances.
  • The players might use a certain action only in certain circumstances. For example, perhaps using a thrown weapon, or intentionally moving to stand in front of another player character, could be prearranged signs for something ().
  • They should not text message each other at the table. It would be too obvious that one is using his phone and the other receives a message.

Finally, and perhaps the best advice, I recommend playing a "hidden identity" board game such as Secret Hitler, which will give players practice in conveying information without revealing which of them are secretly bad guys.

  • 2
    \$\begingroup\$ +1 because I'm always a fan of "this is a solved problem." \$\endgroup\$
    – nitsua60
    Aug 4, 2018 at 21:53

If the players are aware and on board, I would attempt to limit “under the table communication” as much as possible and just let the game continue normally. Design several encounters which with somewhat obvious opportunities for the doppelgängers to achieve their goals. Feed them these opportunities until they catch on and get the job done!

I find under the table communication can really spoil the atmosphere of a gaming session so I actively try to minimize it.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .