A traitorous player can be a really great plot beat in Dungeons & Dragons.
Having a player betray their party in Dungeons & Dragons is one of those plots you never forget, for better or worse. Betrayal works well as a story device, especially betrayals exhibited through characters like Darth Vader and Saruman: traitors who may have fundamentally altered how you felt about the story and character.
However, introducing and playing the trope can present some issues if the party isn't on the same page, and can be a potentially contentious storyline for players to engage with. Navigating a party betrayal takes a lot of tact and planning, especially if that betrayer is a player character. But, at the end of the day, traitors are fun. They're really fun. Here's how to help run them.
Enable PvP In Your Game
There's a pretty standard social contract in Dungeons & Dragons that every player quietly agrees to when they sit down to play: playing a collaborative game. In fact, most (not all) TTRPGs rely on party cohesion to get things done.
A treacherous PC violates this typical social contract. As such, expectations should be discussed during session zero, especially at tables you may not know well.
A betrayal is a story device , not an end to a campaign. In most games, traitor PCs will understand that they likely will not succeed. Make sure you set up expectations accordingly.
Tell your players outright that PvP (player versus player) will be at your table.
Manage Expectations
If you don't want to admit to considering traitor PCs to keep an element of surprise, one method you can use to collect consent from players would be consent forms.
Implementing a question such as "I would be okay with fellow players having ulterior motives" can be a good way to introduce this without giving up the metaphorical gun.
If a player decides to opt out later, then you've done your due diligence by them and can send them on their way with no hard feelings.
In a game where most table issues can be solved by the word "communicate," obfuscating the truth from players may seem a bit uncomfortable, especially if you, as the Dungeon Master, are working with a player. If this idea makes you uncomfortable, do not run a traitor PC.
At the heart of this conversation, you want to be sure that you're betraying the characters, not the players.
You can't control whether or not someone experiences character bleed, but you can try to make sure your players are at least consenting to the type of game they're playing and have some choice in what they do about it.
If a player is going to betray their party, you have to ensure the party can do something about it, otherwise you enter firm railroading territory. This means you should remind the player betraying the party that they may die.
Ideally, you'll know your table well enough that you can pull off a traitor PC. Traitor PCs can go over really well, especially for tables that love immersion and secrets.
Communicate With The Traitor PC Throughout Gameplay
Now that you've decided to go through with the player betraying the party, reach out to them.
Go through expectations and then have them make a backup character. Having a backup can encourage them to be more reckless with their betrayal, and won't endear them to the idea of their character riding off into the sunset.
There are plenty of reasons a player might want to go through with a betrayal. Sometimes it's in character, sometimes it's plot-relevant. Whatever the reason, you should make sure they run any ideas by you first.
If you want a betrayal and one hasn't been suggested, look through your player's backstories and see what can be exploited.
Keep your phones out in case they have a question, or employ note passing. If you're online, open up a private chat, especially if the player is acting as a spy. Don't be afraid to say no or make calls that you think will move the story forward.
Bring Collaboration Back
The obvious choice when dealing with a traitor PC may be to keep them secret.
However, most DMs may often tell you this is not a good idea. Betrayal, even in a game, might feel personal. One perusal of the search results under "traitor PCs in D&D" will greet you with miles of horror stories.
Unless you know your table would love a secret traitor, consider revealing early on that they are working with ulterior motives. Your surprise should be their actual motivation, who they're working for, or what they know. These things will all come out during the campaign.
Letting the players watch the PC backstab them can help mitigate bad feelings by ensuring they have meta-knowledge, but their characters don't! Showcase this by having the player split off from the party briefly and do a short "reveal scene" with them.
This also may endear the character to the players and help them push for redemption for the character, and may contribute to a richer story. Getting a look at the traitor PC and their motives can work well for story-driven games, and you may find the players engage with it.
If you're handling the PC this way, encourage them to reach out to their fellow players if they intend to find out information about them, so the players don't feel manipulated. Again, unless it's acceptable at your table, bringing the collaboration back into the game is a great way to have fun with a betrayal.
Secret Traitor PCs
Consider allowing your players to put the pieces together themselves. Lay clues to their deception, have your players make rolls, and let the traitor roll against them privately. There should always be a way for the players to find out if they should pursue it.
This doesn't mean you should let the party win by virtue of being the majority, though. Some DMs may even ask the table if they want to proceed with a battle, verbally acknowledging player characters may end up dead.
Handling The Traitor PC's Exit
What do you do after your little Brutus enacts the betrayal? Ideally, the character is more or less played the way a regular PC would be, but after the character decides to drop the ruse, there's a question of what comes next.
One idea to handle PC treachery is to have them turn over their sheet to you the moment they reveal they've backstabbed the party. Maniacally laugh, hit them with the NPC beam, and proceed.
This can help keep everything above board, but you may find yourself drawn to the idea of letting the player play out the betrayal. While this may sound good in theory, it may only work for a final battle.
After all, once they've ultimately crossed the party, the social contract of collaboration is over, even if you plan on having the character come back.
Ultimately, a traitor PC can enrich a table's connection with a game. There are lots of success stories, as long as communication remains open, you can create a fantastic BBEG, story moment, or memory for the players in your game.
