Karn surfaced from his waking dream in the midst of a fierce fight. Phyrexian shock troops-more machine than creature-swarmed him. Their human heads and torsos were deeply ensconced within a framework of artifact mechanisms. On draconic legs, they ran. With scythelike arms, they fought. Their horns could impale three men abreast, but they could not impale Karn.

Karn patiently grabbed their arms and ripped them loose. It was the treatment he had given Tsabo Tavoc and now to her children.

The beasts fought on. They couldn't destroy him, but they could halt his advance until more troops arrived. That would be enough to doom everyone aboard Weatherlight.

Growling, Karn knocked down a trooper blocking his path. It landed on its back. Karn stomped on the thing's chest. Metal failed. Flesh oozed out like paste from a tube. This was worse than killing the hounds. These creatures had once been human.

Karn finished the wretched work. Glistening-oil coated him from feet to hips. It poured in a regular rain through the grating. Trying to shut the sound out of his mind, Karn strode deeper. The engine core called him.

Again, the tunnel closed to a single point. It opened in another place and time, but the circumstances were the same. He was killing Phyrexians to defend a friend.

This was a true friend, not like Teferi. This was Karn's first true friend. Her name came ringing back through his body like the toll of a bell. Jhoira. She had saved him from loneliness, and he had failed to save her from Phyrexians. She lay, bloodstained and broken, on the floor of her cell there at the academy (the academy?), and Karn fought in rage against the negator that had slain her. He was not really defending Jhoira, for she was already dead. He was avenging her, bloodily, with a sense of righteous rage.

The killing strokes of that bygone day-how long ago?-elided with the killing strokes Karn would swing in mere moments.

He had reached the engine room-a huge arched chamber. At its center was an enormous engine, ten times the size of Weatherlight's. Buttresses of Thran metal braced a sloping manifold in foot-thick steel. Within that framework surged energies that glowed red-hot. Power coursed from the main engine into countless arteries. Auxiliary powerhouses crouched on the floor around the mother machine. The air throbbed with noise. The engineers were utterly unaware of Karn's approach.

They were almost human-tall, thin, with weighty brains and narrow digits. Their bodies bore slender metal implants. No doubt these were compleated Phyrexians, but they had not been much modified from the human stock whence they had been drawn.

Without pause, Karn strode to them. They died like birds in his grip. How could he do this? Karn, who had stood by while Tahngarth was tortured in the Stronghold? Karn, who had allowed Vuel to make off with Gerrard's Legacy? Karn, who had failed Jhoira in her hour of greatest need?

No, he had not failed. In fact, he had turned back the hour, had turned back even the day. He'd gone back in a time machine-strange memories!-to kill her killer, to save her and the whole academy of Tolaria.

Tolaria! But Tolaria was a myth, less real even than its master Urza.

If Tolaria was a myth, why did Karn remember its destruction? To save the academy-no, to save Jhoira-he had pushed the time machine to its limits and destroyed it all.

To save his one true friend…

The Phyrexian engineers were dead. Gerrard and the others would be dead too unless Karn shut down the engine. There were countless ways, but as Karn read the configuration of power cells, he knew the main core would always restart itself. There was only one way to shut it down permanently.

Striding along the oil-stained flank of the engine, Karn shoved levers upward. Power mounted. One cell began to whine and then the next. Mana superfluids boiled violently. The rumble crescendoed to an angry wail, then a deafening shriek.

It was enough. Karn turned. He ran back the way he had descended. It was an easy trail, marked with bodies. Seventeen engineers beside the power core, twelve shock troops in the passageway, and there, ahead, where clear sky shown through a hull breach, five vampire hounds.

Behind Karn, the core went critical. White-hot fire engulfed the engine room. It burst the walls outward. It flung the doors from their hinges. Pure energy bounded up the corridor behind Karn.

He ran. His feet clanged on the grating. From heat alone, the vampire hound bodies burst into flame. Their glistening-oil blood made a wall of fire before him. White power behind and red flame before, Karn hurled himself through the hull breech. He roared. His bloodied hands burned as he hurtled through the air.

Perhaps, in destroying it all-even himself-he had saved his only true friends.

Then, like a memory solidifying, Karn felt something in his hands. He held on and was drawn away from the incendiary cloud. Black metal retreated beneath his dangling feet. Urborg appeared below.

Karn clung to the forecastle rail of Weatherlight. Fires snapped and burned around his hands and feet, but he held on.

Above the rail, eyes worried within a shock of black hair. Gerrard smiled.

"Karn, you did it. You made it back. I don't know what I would've done without you."

Throughout their flight across the ocean, Rhammidarigaaz had wondered how he would find the second Primeval. Now, as his dragon nations circled above tumbled Yavimaya, he knew.

The Primeval drew him. She lay imprisoned below. Elves had entombed her in the heart of a great tree. For ages of ages, the ancient forest serpent had been a captive to the wood. Magnigoth sap had pasted down her scales. It had permeated her flesh and coursed into her blood and leeched every rebellious impulse from her mind. This dragon, who had breathed forests into being and had flown in a world where mortals were caged birds, this beast was a prisoner of the trees. But not forever.

Bending his fangy mouth down toward the forest canopy, Darigaaz began a long, spiraling dive. His people followed.

The wet heat of Yavimaya streamed across his leathery wings. Beneath the sun and above the treetops, Darigaaz soared. In this time of war and dark revelations, there was too little quiet and beauty. He watched his own lithe shadow as it surged over the canopy. Tree to tree, the image leaped. In its wake came the shadows of the dragon nations. They seemed fish schooling above a reef. Down to Yavimaya they plunged.

She was here, just here, in the massive magnigoth around which they circled. It was a mountain of a tree, three thousand feet tall. Its crown could hold aloft an elven city. Large white blooms spread across the peak and showered gleaming pollen through the air. Gigantic Kavu basked among its branches, letting the sun warm their reptilian blood. Below, foliage spread in four more levels down the huge trunk. Each had its own climate, its own fauna and flora. The base of the tree was a swollen knob of wood that bristled with spikes.

Even glimmering pollen and acrid sap could not cover the sweet, sharp scent of dragon flesh. The magnigoth was powerful and ancient, yes, but less so than its captive.

Darigaaz tucked his wings and plunged through the upper canopy. It was like diving through the algae of a deep pool. Sunlight failed. Wind gave way to stillness. Airy creatures were replaced by giant spiders, staring Kavu, and every skulking thing.

His people descended in a ribbon behind him.

Darigaaz circled the magnigoth trunk. Heat seeped from his skin. Talons dragged through moist murk. Wings brushed the spikes that jutted from the root bulb. There was no true soil here except the humus that ran in a black network among the trees. On that spongy ground, Darigaaz landed. His claws dug in the dirt, and he tucked his wings. With a final flap of leather and a series of soft thuds, the dragon nations of Dominaria landed. They formed a thick ring of flesh around the prison of their ancient lord.