There’s an old card game called Illuminati that I rather enjoyed back in the day. It was a conspiracy-themed game where the cards represented different organizations, like the Boy Scouts or the Mafia, and you built a secret network of organizations controlling other organizations as you tried to achieve world domination. Cards were grouped into “types”, such as “criminal” or “government”, and each type had an opposite type that was considered an “enemy”. It gave you penalties when you tried to have a group control an enemy group and bonuses when you had one try to destroy an enemy group. So when the Mafia tried to control the Biker Gangs that worked well since they were both “criminal”, for example.

The “fanatic” card type was special. Any “fanatic” card was considered to be the mortal enemy of any other “fanatic” card. It was the most realistic part of the game, aside from the orbital mind control lasers of course.