Why do you disappear in Pokemon Mystery Dungeon explorers of time?

Answer 1

You disappear because after restoring time, the paralyzed future is destroyed, and a new, better future is formed. Before the game began you were a human who was partners with Grovyle, and you were born into the paralyzed future. While on a mission to change the past, Grovyle and u were separated and tossed into the past. That is why you find yourself unconscious on the beach at the start of the game. So, after beating the game the future is changed, and you are destroyed. Later, however, dialga realizes that he owes you, and the best he can do is make you reappear, because he trusts that you will continue to do good deeds.