[@Shohmyoh]Maybe look into some ethics or game theory experiments (e.g. Prisoner's dilemma, Ultimatum game, Trolley problem) for inspiration when it comes to the trials? Like say one of the trials involved playing a version of the Ultimatum game where one person divides 100 points between herself and a partner, but the partner can refuse and both of them get 0 points. Rationally, it wouldn't make sense for the partner to ever refuse because they never really lose anything, but putting a twist on the game (say after a certain amount of rounds between differing groups of partners the individual with the least amount of points dies or whatever) could promote the cooperation or subterfuge you want.