Once one has used up the precious amount of 'life energy' granted him in his lifetime, he may be forced to start a new, in a different life. The soul may stay intact, the body is gone forever, returning to dust. Some even choose to start a brand new life on this world when they are bored with their current one. This is a drastic measure and a feat only accomplished through powerful magical means. One should take great care in choosing this path, as there is no return. You need a water lily flower to cast this spell.