Harry Potter FanFiction AU

Question

I am trying to find a Harry Potter fanfiction where he is raised by Sirius while being trained by the Ministry and defeats Voldemort. Then the fanfic starts where he is forced to go to Hogwarts to learn how to be normal. It’s a Harry/Ginny story and in part of it he defeats a Nundu by changing into his Animangus form of a dragon.

Answer 1

This might be "Learning to Breathe" by onoM.

The figure appeared on platform 9¾ in a normal enough fashion, but for the fact that the person now occupying the crowded platform was anything but normal. At nearly 6' tall and about as rigid as a slab of quick-dry cement, he looked nothing like the rest of the students sharing tear-filled goodbyes and boarding the Hogwart's Express. He wore a fitted black t-shirt and loose-cut jeans with black boots. An olive-drab canvas duffel bag was slung carelessly over his shoulder as if it were affected with a weightless charm.

His close-cropped thick black hair did nothing to cover the faint pink outline of a lightning bolt scar on his forehead, and his green eyes quickly scanned the area for threats with practiced ease. Train stations were highly dangerous, no matter how well-prepared one was. Klaxons were going off inside of his mind at every closed trunk and bag, he needed to enter the train quickly.

.....

The War. Had it really ended? Harry had been fighting it as long as he could remember, training for that inevitable clash between Voldemort and himself. And now that he'd clashed and emerged victorious, his mind wouldn't believe that the danger was over....

It was how he was trained, the way he was raised. The finest minds in the wizarding world had honed him into a weapon, and his Godfather Sirius Black had shown him the meaning behind it. The man was as close to him as any father, although he was rather strict when it came to training....

....

When Harry stopped spinning, a blast of dry heat hit him in the face. It stung his eyes, causing him to squint as the coarse desert sand pelted his combat uniform. A dark-skinned wizard wearing a bright purple robe with three gold slashes on the sleeves met him, bowing deeply and then looking around. "Have you brought word of when your Ministry can send wizards? Our villages are being slaughtered by the Nundu, and they send a messenger?" His English was clipped and incredibly fast, a variant known as King's English. He sounded frustrated.

....

He couldn't see his eyes, but knew that his pupils now had a vertical and horizontal slits that formed a crosshair. He knew the creature could see in total darkness with these eyes, but he couldn't even tell them which way to look. Control only ever returned to him after he woke up several hours later, his human form never knowing what he'd done and feeling like he'd just regrown every bone in his body. At least he wouldn't have to worry about the Nundu plague anymore, dragons were immune to every form of muggle and magical disease.

It's apparently kind of a crossover with Full Metal Panic.

Found by searching for Harry Potter fanfic soldier nundu and recognizing the title from having read a bit of it before.