A young man was playing his favorite game and after working very hard, he managed to beat the game, as a reward the game allowed him to create a whole new background for the game and his character in it.
Since the game used the most advanced A.I. tech current in the world, it was possible to do anything inside the game at least within the restrictions of an RPG.
Taking this opportunity, he wrote a vague background for the world before moving on to what mattered, his character background where he wrote a pretty insane background for his self-insert main character who was very special.
What he wasn't expecting was the game becoming reality and overwriting everything.
So now, he would have to live as his main character in the world with the overpowered background he gave himself.
Using this situation to his advantage he would rise to be the greatest of them all in a power fantasy RPG of his own doing.