According to Nordic cosmology, there were nine realms.
Asgard, realm of the Æsir. (Wizards such as Odin and Thor had made their homes here after leaving Earth.)
Vanaheim, realm of the Vanir, the Æsir's bitter rivals.
Alfheim, realm of the Light Elves.
Svartalfheim, realm of the Dark Elves.
Jotunheim, realm of the Frost Giants.
Muspelheim, realm of the Fire Giants.
Midgard, realm of humans. <- (you are here)
Nidavellir, realm of Dwarfs.
Niflheim, realm of mists and the dead, which Oleandra had already briefly visited.
"Of course, I divined what would happen to us if we went to each of the other realms," Oleandra said grimly. "Firstly, Asgard. It's under lock and key, we wouldn't even be able to realm travel there. Secondly, Vanaheim. Nothing but misery awaits us there. Thirdly, Alfheim. Nothing of interest here; already picked clean. It seems that number two and three have already been devastated by war."
Oleandra paused for emphasis.
"And here's where it gets weird," she said. "Svartalfheim, I couldn't divine anything about it. I think they've made their world Unplottable, because realms don't just disappear like that. We won't be able to make it there without their world's coordinates."
"Jotunheim and Muspelheim are both instant death," Oleandra added. "Frozen and burned to death, respectively. If we ever go there, we'll need to take precautions beforehand."
"Which leaves us with Niflheim, Midgard and Nidavellir," Oleandra finished. "Niflheim is a world of stagnation, so there's nothing of interest here but Dementors and dead people's souls. Midgard is where we are right now, so it's useless to divine anything about it. And finally, the world most like ours: Nidavellir. There is mortal peril in going there, but there are also gains to be made. Any questions?"
"Yes," said Draco. "Who are these two?"
"Ginny in disguise, and a passenger," said Oleandra curtly. "Anything else?"
"How long will we be gone?" Stacey asked. "I have work tomorrow…"
"Barely an instant, I think," Oleandra assured her. "I spent a long time in the world of the dead, and barely any time had passed here on Earth while I was away."
Oleandra didn't know for sure if this applied to all of the other realms. For all she knew, maybe time passed extremely slowly in Nidavellir. A day in the other world might even be a thousand Earth years…
Once everyone was ready, Oleandra led them to a secluded area near the Shrieking Shack. Six people would be making the trip; Draco had already sent Crabbe and Goyle away. Oleandra waved her wand and traced a pentagon within a circle in the snow. Oleandra, Daphne, Tracey, Ginny and Draco placed themselves on each vertex, while Stacey placed herself in the centre.
"I'm going to begin," Oleandra said seriously. "You know the nine runes. You've been practising, but make sure to follow my timing exactly."
She took a deep, nervous breath.
"Wunjo, Kenaz, Ansuz, Laukaz, Uruz, Elhaz, Raidhu, Eihwaz, Dagaz!" Oleandra chanted. Each time she called out one of the runes' names, all five of the Wizards assumed its stance rhythmically. At the centre of the circle, Stacey watched on, frightened.
"Let the powers of the stars unite under my standard! I call upon the torch to guide the way. The all-power, the lake of magic, the gateway to the nine realms. Protect me on my journey through time and space, through the omnipresent world tree!" Oleandra chanted without pause. "Open the gate to the realm of Nidavellir."
The instant the last word escaped her mouth, the sun disappeared from the sky, and night suddenly fell upon Hogsmeade. The blizzard settled down; an eerie silence replacing the hustle and bustle of everyday life in the little village. Students and villagers, wondering what was going on, came out of their homes and shops to see what was going on.
Standing tall, a gigantic, illusory tree seemed to reach out to the shimmering stars, but no sooner had it appeared that the light of day and the blizzard returned, as if nothing had happened. Puzzled, and more than a little cold, the curious onlookers returned indoors to the comforting warmth of their homes or shops.
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With the creaking of an ancient wooden door slamming shut, Oleandra and company were flung across space and time, to a place where no Midgardian had set foot for aeons! Oleandra felt as if she had been pressed through a strainer and then stretched like a rubber band to its limits. For a few panicked instants, she felt as though she were drowning in darkness until she realized she had forgotten to breathe.
Oleandra's eyelids fluttered open. Gone was the blizzard; they certainly weren't in Hogsmeade any longer. She looked around to make sure everyone had made it through the gate in one piece: Daphne, Tracey, Ginny, Draco and Stacey were all present. They weren't in great shape, but they were still there. Most of them were groaning and holding their heads, while Stacey seemed to be retching the contents of her breakfast out on the grass.
So far, so good! During the past year, as the group's purpose was to explore other worlds, the Starshower Club had established a set of steps to follow in case its members actually managed to reach the realms beyond Earth. Since they weren't immediately attacked upon arrival, they could get to work.
The first order of business was to get the lay of the land. Oleandra climbed a small hill to get a better view of her surroundings and started scanning the horizon for recognizable landmarks. They seemed to have landed in a grassy plain. White spots dotted the landscape; Oleandra supposed they had to be some kind of sheep. In the distance, a gigantic mountain seemed to scrape the clouds; this seemed like a promising first destination.
But for now, the group wouldn't be doing any more exploring, for one simple reason: they would be awaiting nightfall. The runes here didn't have the same shapes as they did on Earth; since Nidavellir wasn't located in the same region of space, the constellations were different. In order to use runic magic, Oleandra would first need to observe the night sky. Until then, she would have to make do with ordinary Wizard magic!