Playerlist or Setup

[Something_Smart]

In terms of what makes an unfun game: either. Bad setup can make you feel like the game is stacked while it's going on, or run in circles chasing incorrect mechanical arguments, or just directly make the game not fun. Bad players can... well, that one's kinda obvious.

In terms of what makes an exceptionally fun game: neither, really, but they both contribute. A good playerlist is conducive to a game being great, but it's possible to have really meaningful experiences with people you hardly know, or even people you didn't like playing with in the past; it depends on the specifics of the game. Similarly, a good setup makes a game more likely to be great, but it still has to play out in an interesting way (even great setups sometimes have all their cool roles killed off early or their interesting interactions never happen).