The pack game refers to TCG's(trading card games.) You can play with 2 or more people, but the more people the better. I prefer using magic the gathering cards. You open your pack face down and shuffle it. Now pick a varying random statistic on the card (set number, alphabetical order of the name, amount of vowels on the card, mana cost, BE CREATIVE!) once you have decided the statistic, everyone flips their card over. Whoever does not win that round must tear the card that they flipped over. Repeat this process until just one person has card/s left.
Dude, i totally just beat Mitch in the pack game, he had to rip up a black lotus!