"Neither can live while the other survives..." Yeah, that sounds like Harry Potter, alright. Except no, it really doesn't. In this story, we choose a far more likely candidate than Harry Potter for the prophecy.

Currently Entering Year 2: As a 15 month old child Harry Potter survived against all odds. However, what will happen when the dark lord resurfaces with two goals in mind, reclaim power, and kill Harry Potter. However, despite being terribly abused as a child, it will be a powerful, cunning, Slytherin Harry Potter that will await the rising challenge of Lord Voldemort

A twist of fate sends Harry down a much darker path. The question is not how far he will fall, but how many others he will take with him.

... and Harry did not have a scar when he came to Hogwarts? Completely AU, partly OOC, Dumbledore/Weasley bashing,

A Potions accident in his sixth Hogwarts year takes Harry back in time. Will he be able to save his parents and change the timeline? Completely AU, partly OOC, sick!Harry. HP/GW, LE/SS not JP! , MM/AD

Revenge is the misguided attempt to transform shame and pain into pride. Being forsaken and neglected, ignored and forgotten, revenge seems a fairly competent obligation. Good thing he's going to make his brother pay. Dark!Harry! Slytherin!Harry! WrongBoyWhoLived.

People rally to a just man, as Umbridge finds when the DA follows Harry to arrest her and demand that the Wizengamot try her for torture. When Dumbledore seeks atonement in battle against Voldemort Harry inherits his power and his responsibilities. Harry must learn to wield those powers in a world where law and justice have powerful enemies and many must atone for injustice done.

An AU story where Harry is trained by an assassin from the age of eight. New challenges will face him and canon ones will be altered and completely dismissed too.