The next morning, after swinging by the kitchen to get a cup of coffee and a scone from Hans, the head cook, I hurried to the main hall.

Somehow, I managed not to spill a drip of coffee on my thin black sweater.

Victory!

That didn’t save me from the crumbs, but at least they could be brushed off. At one point, a raisin fell into my shirt and I had to stop to shake it out.

A sparkling little mouse scurried out from a hole in the wall and grabbed the dried fruit that dropped to my feet, and then hurried back to the hole in the wall.

“A glitter mouse?” I murmured. “Weird.”

The little creature turned back and glared at me with beady black eyes, as if it could understand me.

“Sorry, you’re not weird,” I said. “You’re lovely.”

The mouse nodded her little head, which sparkled like diamonds, and carried her raisin off into the hole in the wall.

“All right, then.” I popped the last bite of scone into my mouth and kept heading toward the hall.

Cade was waiting for me by the time I arrived. I finished the last sip of my coffee and set the cup on the little tray set into an alcove in the wall. The cup would disappear back to the kitchen, a luxury that delighted me to no end.

“Ready?” Cade asked. He wore the same dark tactical gear as he had last time.

“As I’ll ever be.”

We walked out into the cobblestone courtyard as the sun peeked over the horizon, lighting the gray morning with a golden glow.

This time, the climb down the cliffside was a little less scary. I still wouldn’t do it as a hobby, no matter how nice it would be to stroll the beach down below, but at least I wasn’t a shaking mess when I reached the bottom.

“This way.” I led him toward the cave, which was still pretty dark this early in the morning.

I stopped near the middle of the cave, gazing around the space, then pulled the bag of carved stones out of my small backpack. I dumped them into my hands, then handed half over to Cade.

“These are supposed to help us,” I said.

“How?”

“No idea. But the scroll said it would become obvious.”

“All right.” He studied his stones.

I bent my head and studied mine. I had four. One looked like an arrow, another like a face, the third like a sun, and the fourth a bird.

I tucked the one with the arrow back into my pocket. If I was understanding the scroll correctly, I’d need that one for later, to help get through the realms of the gods.

The last three were still a mystery though.

I clutched them in my hand and began to pace around the cave. It was a huge space, several hundred feet wide and just as tall. The mouth was enormous, allowing more light to enter as the sun rose.

The carving on the wall that I’d seen yesterday caught my eye. I tilted my head and studied it, then pointed at it. “That looks like one of my carved stones.”

Cade joined me, peering up. “We should look for more carvings, then.”

“Agreed.”

We split up, pacing the space, looking in every nook and cranny for more carvings. On the far left, I found a huge hole in the wall. It led back to an underground spring. The water glittered with bioluminescence, and it allowed me to see that the stream stretched far back into the cave.

Cool.

I turned from it and kept searching. A moment later, I found the sun-shaped inscription high on the wall near the back entrance to the stream.

“I found one!” I called.

“So did I,” Cade shouted from across the cave.

Further inspection revealed a tiny little slot in the wall beneath the carving.

I dug the sun stone out of my pocket and put it in the slot. Magic sparked over my fingertips.

“Jackpot.” I turned to Cade. “Try to put your stone in a little slot in the rock, if you can find one.”

A moment later, he called, “It worked. There’s magic here.”

It took us fifteen minutes to find the rest of the carvings and insert our little stones into the slots. I didn’t find one for the bird stone, but maybe I’d need that for later. As soon as I placed the last one, the air shimmered with magic.

I turned from the cave wall to face the great open space. Magic lit the air, swirling with a golden glow and coalescing on the ground near the tools.

They rose up, dancing on the air, along with the abandoned pieces of wood.

“Amazing,” Cade said.

“Just like that movie. Sleeping Beauty. Where the fairies make the house clean itself and everything moves around.”

In front of us, the wood began to assemble itself on the surface of the water in the middle of the cave. Tools pounded and banged, building the ship in front of our eyes.

First, sparkling magic lifted a heavy piece of wood and connected it to two curved end pieces. Bow and stern, I had to assume. The ship floated in the air as the glittering magic added planks to the sides, each one overlapping another, perfectly fitted and carved. Then some crosswise pieces were added inside. I tilted my head. They looked a bit like slender ribs. Finally, magic added a giant hunk of wood to the middle of the boat. Last, a mast was inserted into it.

Soon, a complete Viking ship had built itself for us.

“Holy fates,” I breathed.

Then it drifted on the surface of the water, headed toward the stream that stretched back deeper into the cave.

“Uh-oh. Come on!” I ran after the boat.

Cade caught up to me as I hurried to the edge of the water, where the boat waited. Very convenient.

I leapt inside, stumbling a bit, then righted myself.

Cade, of course, was graceful as ever.

As soon as he was in the boat, it took off, drifting down the glittering water that illuminated the cave around us.

“Bioluminescence shouldn’t live here,” he said.

“That Viking boat shouldn’t have built itself for us.” I shrugged. “Magic.”

He grinned.

The ether sucked us through. I gasped, reaching out for Cade. My hand met his strong arm, and I clung to him. He gripped me around the waist as the boat rocked through the ether.

A moment later, the sun blazed in our eyes.

Yggdrasil rose tall in front of us, so impossibly huge that I still couldn’t conceive of it even though I’d been here yesterday.

“Fates of all,” Cade murmured. “The World Tree.”

“It’s something, isn’t it?” I studied our surroundings. I could no longer see the Norns’ cottage or their well, which meant that the river had delivered us somewhere else along the base of the great tree.

Fields stretched out around us, and the bottom of the tree was ridged with valleys made by the roots sinking into the earth. We floated on a river that drifted lazily toward Yggdrasil. The boat didn’t seem to need any propulsion because it moved along without using the sail or the oars resting against the sides.

“From what I’ve learned, there are nine realms of the Viking world,” I said. “We were on Midgard, where mortals live. Now we have to make it to the realm of the Valkyrie. But to do that, we must pass through several other realms, going higher and higher up the World Tree.”

“Do you know where we start?”

I pulled the scroll out of my bag just to confirm, then looked up at him. “We must find Hverglemir, the Roaring Kettle. Also known as the Source of Many Rivers. It will take us to the next realm.”

“Does it say which realm that is?” Cade asked.

“Unfortunately not.” Which was really very unfortunate. Some of the realms were supposed to be great. Others, not so much.

The river wound around the huge roots that sank into the ground. They rose like mountains on either side of us.

As we rounded a bend, something massive shifted in front of us.

One of the roots was alive!

A huge serpent’s head turned toward us. Gleaming green eyes pierced me where I stood, and a tongue flicked out. It looked almost like a dragon, actually.

To the left of the serpent, a huge eagle turned to look at me. Surprise widened the eagle’s eyes, and it hopped behind the serpent’s coils. Or maybe they were roots? Either way, the bird was definitely hiding.

“I am Níðhöggr. What do you want here?” the serpent hissed.

“Um, I’m Bree Blackwood.” I pointed to Cade. “That’s Cade.” I didn’t mention that he was the Celtic God of War. Better not to mention anything violent in front of a serpent who probably considered me a snack. “I’ve been given a map by the Norns to take me to the realm of the Valkyrie.”

Interest gleamed in the serpent’s eyes. “The Valkyrie DragonGod. How interesssting.”

“Thanks. Could you tell us where Hverglemir is located?”

He nodded, jerking his head toward the right, in the direction that the water was heading. “Just down that way. Get a move on.”

“Thank you.” The nervous sweat that beaded on my brow cooled as we drifted by the serpent.

His green eyes sparked with interest as we passed. “Go on, now.”

“Yep. We are.” I gestured awkwardly at the water. “Just as fast as the water will take us.”

“Hmmm.” The serpent shifted, a gesture that would almost strike me as nervous.

That was weird. Did he want us gone?

At least he didn’t seem inclined to attack or anything. All the same, I stayed tense. Not that I could fight him. His head was the size of a football stadium.

But I’d go down swinging.

I watched him as we drifted out of sight, waving goodbye.

Finally, he was gone.

My shoulders slumped, and adrenaline drained from my muscles, leaving me shaky.

“He was nice,” Cade said.

“Yeah.” I laughed. “Still scary though.”

“Giant serpents usually are.” He walked toward the bow of the ship to look out over the twisty river that wound around the trunk of the tree. “Why was he with an eagle? Do serpents and birds usually get along?”

The memory of the eagle hiding himself flashed in my mind, along with a story I’d read. “Yeah, that’s really weird, actually. The only eagle that I know of is the one who lives at the top of the tree, while Níðhöggr, the serpent, lives at the bottom.”

“But now they’re together.”

“Seems so.”

The sound of roaring waves caught my ear, and I leaned over to try to see around the bend.

A moment later, massive rapids came into view, the water white and roiling. It splashed and bubbled as boulders broke up the tranquility.

“We’re nearing the central rapids,” I said. More rivers poured into the area. Or out of it?

Whatever the case, our boat was shooting towards it.

“Down!” Cade said.

I threw myself to the deck, huddling near the mast. Cade joined me, wrapping his big body around mine.

Protecting me?

My chest warmed.

The boat bucked and thrashed, throwing us up into the air. We went airborne for a second, then crashed down on the deck. The rollicking ride continued as the boat hurtled through the rapids.

Then everything went dark.

Heat blazed.

The ride smoothed out.

I shook my head, trying to clear my vision, and shoved at Cade. “Move it.”

He grunted and lifted himself, rising gracefully. I scrambled to my feet, my heart plummeting as I took in our surroundings.

The air was boiling hot, and the river bubbled. Steam sizzled where the water hit the shore.

“Is that lava?” I pointed to the crumbly, blackened shore.

“I believe so.” Cade drew his sword and shield from the ether.

I squinted through the steam that rose up wherever the river hit the molten magma. All around, it was dark. The only light was provided by the lava that glowed red. The land in the distance gleamed crimson and black, like deadly waves.

“How has this water not evaporated?” I asked. It was just a river. A wide one, but there was more lava here than water, and the heat was unbearable.

“Magic,” Cade said.

I grinned at his repetition of my word, though it didn’t lighten my nerves.

“This has to be Muspell, the land of the Fire Giants,” I said.

“It feels safe to assume that.”

“I don’t know much about them.” The scroll hadn’t given explicit explanation of what would happen as I went through the realms—just that I had to make it through, continuing on my journey up the World Tree and through the godly realms until I reached that of the Valkyrie, which was near the top. The water had led us though some kind of portal, which had taken us to this realm.

“At least the boat is still moving.”

“We’re supposed to stay with it until it leaves us, I think.”

“Leaves us?”

“I have no idea what that means, actually. I doubt it’s good.” I drew my sword, not sure that I could actually fight a Fire Giant with a sword. But it was my safety blanket, and I wanted to clutch it tight.

When the roar rent the night, I jumped. The sound vibrated in my chest, like I was hugging a jet engine.

I spun around, searching for the source of the noise.

The monster grew out of the ground a hundred yards ahead of us, forming from the lava itself—red and black and terrifying. Blazing ruby eyes sought me out, and the beast raised its fist as it howled.

My stomach plunged as it ran forward, pounding toward us. Eighty yards away.

Sixty.

Forty.

Sweat broke out on my brow.

As I tried to call on the water around me, hoping to use it to douse the giant’s heat, Cade hurled his silver shield at the giant’s head.

The metal gleamed as it flew and sliced through the giant’s neck, sending the head flying and the body toppling to the ground. The crash made the land shake and the water around us thrash.

My magic struggled within me, but I managed to get ahold of the water as another giant built itself out of the lava on the ground. Then another.

And another.

“Oh fates.” I aimed for the nearest giant, then shouted at Cade, “Take the far ones!”

“On it.”

His shield flew through the air as my water rose up in a wave. It was a careful balance not to take all the water from the river and leave us stranded on the bottom. We had to keep traveling, hopefully far away from these beasts.

My wave crashed against the giant, sizzling and steaming.

The massive creature stumbled, almost going to its knees. The molten lava hardened to black stone, making him brittle and unsteady on his feet.

Yes!

Then the creature righted itself, picking up its pace as it hurtled toward me.

Crap! “They’re too strong!”

My water wouldn’t work against lava. Not unless I had an ocean to draw from. Which I didn’t. And from the way my magic struggled inside of me, weak and temperamental, I probably didn’t have the control for an ocean anyway.

“And there are too many.” Cade caught the shield that had returned to him and pointed toward the others. They raced for us, thundering across the ground as we floated by on the river.

Going too slowly. Like we were vacationing at a hotel with a Lazy River pool.

In hell.

Cade hurled his shield again. As it beheaded another giant, my mind raced.

How could I fight them? Not with a sword—they were a hundred feet tall and made of molten rock. Nor with water.

Cade caught his shield on the return.

And the earth dropped out from under us.