Tom Riddle took twelve years to form a plan to conquer the world when wandering as a spectre. This plan needed the one loyal family whom he threw away to succeed. Lucky for him, they did not return the favour.
Harry grew up with his godfather, Sirius Black the convicted murderer, on muggle streets. He hated to see his godfather miserable, and was willing to do anything to change that. Even if it meant he had to meddle with time, and give his place in his godfather's life up for a better, more innocent Harry who knew nothing of the dark. Book 1 of the Becoming Infinite series.