[Spoilers] IU and Park Myung Soo play mind games on 'Running Man'

At the beginning of the episode, players were asked to choose between two cards: the lambs or the wolves. Along with that choice, each individual picked an expected ratio for the final number of lambs versus the number of wolves, which they would have to work to maintain throughout the course of the episode.

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The winners from each round of games would get the chance to find out the standing ratio at that point in time, along with an opportunity to switch their own card! The winner would be the one who picked the correct ratio of cards at the final tally. Although many cards changed hands and several members crossed the line between the two sides, the final victory went to the 'Monday Couple' of�Song Ji Hyo�and�Gary!

Although the focus was on mind games, that didn't mean that this episode didn't get physical -- in fact, it gave us one of the most nail-biting nametag ripping challenges yet!

Check out the full episode below!