Mandatory Disclaimer: Don't own the Harry Potter and Shingeki no kyojin series, they are owned by J.K. Rowling and Hajime Isayama respectively. I am just playing in their sandbox of creative ingenuity.
Prologue
The Nightmares That Plagued His Mind
"How did it come to this . . . Why has everything been taken from us? . . . Our lives . . . our dreams . . . Everything."
"Damn you! Damn you all TO HELL! I REFUSE TO DIE LIKE THIS! I'LL DRIVE THEM ALL OUT! KILL THEM WITH MY BARE HANDS! . . . DO YOU HEAR ME?! WITH MY BARE HANDS!"
Harry woke up gasping, his mind still reeling from the gruesome nightmare that plagued his mind. Ever since the resurrection of Voldemort and his unwilling participation, he had begun having the same nightmare of the same person (Eren Yeager, his mind supplied) and every single one of them just as gut-wrenching as the last.
What does the dream mean? He had asked himself that same question, spent time pondering away on it, looking for an answer where seemed none.
Why is this person so important? What made him important?
Even now, as he sat amidst friends in the grand hall of Hogwarts, he barely paid attention. As he sat, eyes drawn partially closed, lips pulled in a frown, fingers clenching and un-clenching, he hoped - no prayed - for something to happen, for the answer to his endless question to appear.
And somewhere in another world, a whole different dimension, a dark haired boy with major anger issues slipped on a wet branch and fell, landing hard on a rather unsuspecting muddy boot . . .
A one-shot which will continue depending on the amount of positive reviews it get.