We played with just 2 people because the other scheduled group didn't show. I think there are options for private rooms.
Exactly. You don't have to have any sort of minimum, but usually, the more people are involved, the more it helps. I have gotten lucky and only had the people in my party sign up for our rooms so I never had to share. Then again, if it's just two of you and no one joins you, you can always ask your puzzle master if it's just the two of you and you guys get stuck.
There isnt a minimum but when you sign up other people could be signing up for the same time slot so even if just 2 of you go, the chances that other people will be there is high.
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