Fics like Praeparet Bellum (Prepare for War)

The ultimate betrayal sends seventeen year old Harry Potter spiraling six years into the past, de-aged to eleven, but retaining his young adult memories of the brutal Second Wizarding War. Determined to end the war before it starts, a war-torn Harry is Slytherin! Grey! Independent! Powerful! and Cunning! Includes Mentor!Snape, Hufflepuff!Neville, and Ally!Draco Also, I was too lazy to separate the chapters, so it's all shoved into one. Be warned. Abandoned, but still very good in my opinion.

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