Forgive me if I have not grasped the ideas and intricacies of the Many Worlds theory. If I don't quite understand it all it's probably because I'm 16. My theory goes like this: According to the many worlds theory, every time a sentient being observes the outcome of the a particle in superposition the superposition breaks down and the universe splits into as many universes as there are outcomes in the probability of each result of the superposition. Every being's conciousness is duplicated and distributed throughout the resulting universes (naturally). When a person dies, I believe that, from the perspective of the victim, their conciousness will only end up in a universe where they can observe that universe. Therefore, when there is an outcome where someone has a chance of dieing, they will only observe a universe in which their particle configuration enables them to survive. The implication: From every person's point of view, they are immortal and invincible. You may observe other's deaths but not your own.