71

Back Door

The cave resembled a narrow slit, just wide enough for a person to pass through.

After coming ashore and entering the cave, Forseti wrung the water from his clothes, infused his legs with divine energy, and sat down to rest, deep in thought.

Before today, he had heard tales of the ferociousness of the four-horned goat but now understood firsthand why it was known as Asgard's most dangerous beast.

In all the Nine Realms, aside from giant dragons and polar ice beasts, few creatures rivaled its strength.

Capturing a four-horned goat alone was near-impossible for most Asgardians, let alone him.

It seemed participating in the hunting festival was out of the question.

Forseti sighed quietly as he sat at the cave entrance, realizing the passage extended deeper into darkness, its winding path shrouded in mystery.

After some contemplation, curiosity piqued him, prompting him to stand and venture further into the cave. He summoned a glowing holy light in his palm, illuminating the surroundings like a gentle bulb of light.

Holy Light Illumination was not a combat spell but rather a utility spell not recorded in sacred tomes, obtained as a reward for past deeds of vengeance.

It served its purpose well, offering clear visibility without straining the eyes—an attribute Forseti found somewhat dubious.

The cave proved longer than anticipated, minutes passing without reaching its end.

Suddenly, rounding a bend, a faint glow ahead caught his eye.

"Hmm?" Forseti paused, extinguishing his illumination spell and confirming the presence of light.

Intrigued, he quickened his pace, eager to investigate.

Another turn widened into a spacious cavern, housing a suspended luminescent object.

The object, a transparent tetrahedron, hung mid-air, its sides emitting soft, rhythmic pulses akin to breathing.

What is this?

Forseti marveled, cautiously approaching the tetrahedron.

Assured of no immediate danger, he observed as the tetrahedron remained undisturbed, its rhythmic pulses continuing.

After a while, he located a nearby stone and picked it up.

Gripping the feldspar, he prodded one side of the tetrahedron.

The prodded side rippled like water's surface, the feldspar managing to pass through albeit with considerable resistance.

The tetrahedron trembled slightly.

Forseti quickly retrieved the stone, finding it unchanged as if nothing had transpired.

Pondering further, he prodded the tetrahedron again, achieving the same result as the feldspar passed through to an unknown space within.

Transparent as crystal, the tetrahedron allowed visibility of objects passing through to its interior. Yet, Forseti discerned no trace of the feldspar from his vantage point outside.

This mechanism bore resemblance to placing objects into Sanctuary space.

Frowning, Forseti contemplated, prodding the tetrahedron once more.

As before, the feldspar traversed with resistance, disappearing into the tetrahedron's interior. However, inspection revealed nothing within.

It appeared the tetrahedron accessed an alternate space, similar to Sanctuary.

Unexpectedly, the feldspar emerged enveloped in lava, molten rock flowing into Forseti's hand as he withdrew the stone.

Lava?

Had there been nothing within moments ago? Could this tetrahedron connect to four distinct spaces?

Forseti blinked, recalling Loki's references in the "Thor" movies to numerous "back doors" between the Nine Realms, offering swift travel across distant realms.

Loki was notorious for exploiting these back doors, once ushering Frost Giants through one. Thor and Jane had also used Loki's back door to journey to Svartalfheim, realm of the Dark Elves.

These back doors essentially were spatial rifts.

Could this be a back door?

Forseti ruminated, recalling that Thor had accessed Svartalfheim through a slit on a small island.

Considering this, he tentatively concluded this luminescent tetrahedron served as the back door Loki spoke of, linking four realms within the Nine Realms, including Muspelheim, home of the Fire Giants.

If magma had emerged, then this place must also connect to Muspelheim.

Svartalfheim, Muspelheim—what remained of the two sides?

Could one lead to Midgard, Earth?

Excitement surged through Forseti. Determined, he retrieved another stone and prodded the tetrahedron.

One side opened to magma, while another drew forth water, the stone dripping wet upon return.

The remaining sides led to unremarkable spaces, one seeming peaceful and open upon entry and exit.

After brief hesitation, Forseti resolved to explore both remaining sides.

Selecting one at random, he treaded cautiously.

The resistance felt akin to passing through liquid mercury or even air.

Upon emerging, Forseti gasped, momentarily breathless.

There was no air here... Forseti silently cursed. Though discomforted, he, as an Asgardian, could endure the vacuum of space for a time.

Aside from the suffocating sensation, gravity seemed notably weak.

Turning, Forseti noted the tetrahedron behind him and a cavernous expanse ahead, an exit visible to his left.

Carefully proceeding along the route, he encountered a narrow passage that necessitated his hammer's strength to breach before continuing.

The journey proved longer than the slit on the island.

After approximately half an hour, he glimpsed light ahead.

Exhaling with relief, Forseti hastened forward.

While Asgardians could survive in space, the environment was far from comfortable. The preceding passage had tested him, and had it not ended, retreat would have been his only option.

Turning another corner, a hole emerged.

Quickening his pace, Forseti stepped through and abruptly widened his eyes: "This—"

Before him hung a vast blue planet, suspended high in the sky...

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