Mafia, a game where 3 people are selected randomly, and must discuss who they want to be killed. The person may be killed, or a guardian angel may have protected them from death. The aim for innocents is to kill the 3 mafia members. The aim of the mafia is to kill all innocents and the guardian angel.
You see in this how strategy is key.
What a great way to present this game for the first time :)