The World's Worst War mobile campaign promoted two new spicy snack foods in Japan through a multiplayer mobile game. Players used mobile phones to join the online armies of either "Tyrant Habanero" or "Satan Jorquia" by inputting access codes from snack packages. They recruited friends to grow their networks and received SMS updates on battles. The campaign was a success due to allowing opt-in social interaction and recruitment that engaged players through the preferred mobile communication channel of SMS.