What are the chances of getting antag role?

Ive been wondering about this one for a while now, can anyone tell me?


It’s going to be dependent on several factors, here are some:

  • What is the round type? Your chance of being a round start antag is 0% on extended.
  • How many players are in the round? Some, possibly all, round types scale the number of antags based on the number of people in the round.
  • How many people have the relevant antag type selected in their character’s settings? If you’re somehow the only one with initial infected selected and it’s zombies, well congrats, you’re the antag. Though I think the game checks if there are enough people willing to be a specific antag before deciding on a game mode.

I don’t think your selected job options have any impact on you being an antag. In SS13, (at least on the server I played on) antag status was decided before job role and if you didn’t have a role selected that could be an antag but you were selected to be an antag, it would just make you an assistant.

Putting that all together into an example, say that there are 50 total players and 5 nukies, one of them being a nukie commander. If 20 people had both nukie and nukie commander selected as antag options and no one else had either selected, then each of those 20 people would have had a 25% chance of being an antag.

I remember poking at the source code to try and answer some of those questions myself. This is almost all from memory, I’m not a skilled programmer, and I’m unfamiliar with C#, so I might as well be wrong. And if I’m not wrong now, I’ll be wrong in the future, when things change.

The odds of Secret being any particular game mode are ~82% for traitor, ~8% for nukies, ~8% for extended and ~2% for zombies. That is, assuming all requirements are met, like minimum player count.

I am almost sure that first Captain and HoP roles are distributed, then the other heads, then the other characters, and only then antags. But this is what I’m least certain about.

Now here you can see the numbers for any given game mode:


For traitor mode, it seems about 10% of the players will be traitors (capped at 12). For zombie, 10% will be initial infected, capped at 6.


The number of nuke ops goes from 3 to 5. And this seems different from the other modes. Maybe nukies are selected before role distribution?

Anyway, please correct me if I’m wrong!