Sisyphus

Sisyphus is a Harry Potter fanfic by esama, in which Harry gets a second chance to relive his life after dying in the final showdown against Voldemort. Seeing his predicament as a blessing, he eagerly decides to make changes in order to save those he had loved and lost, but not all goes according to plan...

When Harry wakes up in his almost-eleven year old body, it is both a blessing and a curse. There he is, in the hut on a rock, his aunt screaming at him, his uncle glowering at him, with Dudley blubbering something in the back - and suddenly he has the chance to make things right. He can save Remus and Tonks and Fred - he can save Sirius, save Cedric, save everyone.

Compare Oh God, Not Again for another take on a Peggy Sue Deconstruction Fic. In fact, it may help after this one.

Tropes used in Sisyphus include:

Beige Prose
Blessed with Suck - Harry quickly comes to view his situation as this.
Darker and Edgier
Death Is Cheap
Death Seeker - Harry, by the end. Oblivion Seeker would be a more accurate term, as death is meaningless and an utter curse for him.
Deconstruction Fic - Against the popular 'Superpowered Harry goes back in time to the start of his Hogwarts years' genre.
Diabolus Ex Machina - Whenever Harry tries to change something for the better or otherwise act differently, sooner or later he ends up dead for his troubles and at the start of another loop.
Downer Ending - And everything starts again.
Fate Worse Than Death / High Octane Nightmare Fuel - Harry is condemned forever to relive his life, even when he finally GETS IT RIGHT. There is no escape.
Groundhog Day Loop
Lighter and Softer - The loops that Harry spends pranking Hogwarts, some of them with Fred and George.
Mind Screw
Peggy Sue / Set Right What Once Went Wrong - What Harry wants to do. Averted, hard.
Shoot the Shaggy Dog - Harry finally defeats Voldemort, goes on to marry Ginny and have a family, and dies of natural causes in his old age. If you think that the loop is finally broken, you are wrong.
The Many Deaths of You - Shadowgate would be impressed by the myriad ways that Harry meets his demise, several of which are repeat offenders:
- Voldemort (at least four times)
- The Basilisk (more than four times)
- Quirrell (at least three times)
- Dementors (more than four times)
- Overdosing on potions
- Suicide (more than twice)
- Fenrir Greyback
- The Ring Horcrux (twice)
- Being literally stabbed in the back
- Toxic smoke
- Being mauled to death by Remus
- Executed by (presumably) the Ministry of Magic
- A backfired spell
- Walking through the Archway of Death
- Burning himself and the Dursleys alive
- Burning the Forbidden Forest down with himself in it
- Being killed by Dumbledore himself
- Putting himself into a coma and later being taken off life support
- Old age.
You Can't Fight Fate