Zef flew across the rooftops.

It wasn’t the elegant soaring of the greathawk, nor even the ponderous laboring of a vynorn. His was a sprint across shingles and thatching, lurching and leaping from one unsteady foothold to the next.

"Fly too fast, Zef," his brother often told him, "and you'll break more than a wing."

But he couldn't slow, and not only for the thrill of moving swiftly. A storm was building, and no ordinary storm. Rain pelted sideways. The winds whipped around, undecided which way to blow. Like vines, sharp twisted around his pumping legs, making the run across the slick tiles more treacherous still.

But Zef didn't slow. He couldn't. Not if he was to keep his brother alive.

Lightning flashed, and the following thunder was so loud and swift he flinched and missed a step. His stomach soared as he slid down the angled roof, the edge rushing toward him.

Zef scrabbled on the tiles with his free hand, nails breaking, fingers scraped bloody. His feet kicked out to find any leverage. Tiles flew loose.

He kept sliding.

Then something solid jolted against his feet. Sucking in a breath, Zef looked down. The chimney had saved him.

No sooner had he registered he was still alive did he open the hand at his chest to look at what he clutched in it. The vial, filled with a milky luminescent liquid, was whole, the seal unbroken.

Zef breathed a sigh of relief, then levered himself upright. Even now, he couldn't slow. Gail's breaths had sounded like the wood rattles they had played with as children, before the furystorm came that changed their lives. Given that they barely had enough food each day, they couldn't afford a healer, but the kindly soothsayer who stopped by now and then had instilled a dire warning into Zef.

"If he cannot restore his air aura," she’d said, "he won’t last the night."

That had been earlier that day, and it had taken until past dark for Zef to locate the air aura and steal it. Those rich enough to afford the sacred substance were difficult to infiltrate, but Zef had had his eyes on the Lokius estate for months. He'd been planning a more lucrative heist, but his brother's life was worth far more than new clothes and shoes.

No sooner had Zef risen, however, than a clap of the thunder had him crouching again. His ears rang with the boom, and the lightning spotted his vision with afterimages. But it was the shadow darting through the dark sky above that had him looking up.

Something else flew through the night.

The creature disappeared for a moment behind the island of Pinnacle above, then reappeared on its other side. Despite his urgency, Zef froze in place. Light aura shone from the beast, so he could see it stretched the length of the town plaza three times over. Its body was sinuous as it slithered through the air, and four wings, each even longer than its body, flapped to keep its massive form aloft.

Zef had never seen it before, but he knew it all the same. The Guardian of the Sky Isles defied the furystorm this night.

He tore his eyes away from the majestic beast and clambered on, but he couldn't quiet his imagination. Furystorms whipped up every year, and all knew the Furies rode upon the black clouds. If not for the Guardian and the masters of the Aedis above, the demonic spirits would spread their destruction down to the world below. Even now, accidents were prone to happen, as he knew all too well.

Zef had glimpsed an eternal battle, and though it should have put fear in him, his spirits lifted instead, and his legs ran all the faster.

His brother would survive this night. Zef would reach Gail in time, and he would breathe in the aura his body lacked. He had to believe it was true.

But afterward, then what? Gail would be better for a month, maybe two, then begin to decline. He needed healing, permanent healing, so he could follow his many curiosities, as he once had when they were young and he wasn't so sick.

Zef knew where he needed to go.

Up. Up to Pinnacle.

The thunder boomed, and the rains poured, and the Furies howled across the night, but he no longer flinched. Hope burned in Zef, bright as the sky spirit he'd glimpsed, and held him aloft as he ran to save his brother.