Social dilemma games that treat cooperation and defection as a dichotomous behavior tend to oversimplify the potential complexity of human decision-making and natural strategies in such situations. Tit-for-tat is proven to be one of the most effective strategies in the Prisoner’s Dilemma, but it quickly breaks when we start treating the level of cooperation as a continuous dimension. Social dilemmas also tend to focus on either a conflict of interest between the individual and the group, or between two groups, but rarely integrate the two. We propose a new social dilemma, called Flood Defence, where participants must distribute resources between their own group and an outside group with the option to keep resources for themselves. In our study, we aim to investigate the natural strategies people opt for in a dynamically changing social environment. Outside of one real participant, the rest of the players follow predetermined strategies, cycling through all the potential combinations of in-group and out-group favoritism-driven resource allocations (involving selfish strategies will be part of future research). Data from a nine-round game will be analyzed to identify the most prevalent naturally arising strategies, which then will be examined with questionnaire data along the factors of the Big Five, Dark Triad, and BIS/BAS scales to determine if these traits have an influence on our strategies in an inter-group social dilemma situation.