I find it's best to have a group of 4-6 people. Any more than 6 just causes confusion because you can't keep up with who is looking for and finding clues. Usually, the Escape company will try to pair you with another group, which is what we did in Chattanooga. It's not awkward at all not knowing the other people because, once you're in the room, you're all working together to solve the clues.
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