Editing Toaru Majutsu no Index:Crossover Extra (section)

===Part 5===

“So that’s what’s going on.”

Loki, the man known as an evil god, leaned up against a stone wall in Asgard and faced the giant wolf named Fenrir.

Fenrir could be seen as his child, his greatest masterpiece, or his anti-god weapon.

“I am more sensitive to most when it comes to this world’s destruction. It comes with how I was created. So there is no mistaking it.”

“The sea is the boundary between worlds. It surrounds our territory and possesses the power that separates us from the truly foreign.”

The Norse world was composed of Yggdrasil and the nine worlds, so it had an extremely simple structure.

It was just one continent with the world tree at the center. After that, there were only the various worlds at the end of the roots and branches.

Then where was the sea?

That was simple: it surrounded that one continent. Or more accurately, it was a massive ocean with a continent floating in it.

“That is why Odin can’t retrieve the souls of the humans who die at sea. The sea is the mouth of death, but that is because the people it swallows are dragged into the truly foreign. Sea Goddess Rán is the one acting to prevent that.”

“You are the one who summoned those heroes from truly foreign worlds. Did you not know what would happen if they decided they wanted to go home and tried to connect to those truly foreign worlds once more?”

“Oh, c’mon. I’m the evil god who tried to change the outcome of Ragnarök. That was enough to satisfy me. Do you really think I had predicted what would happen after the battle?”

“…”

“But in a way, I suppose this could be used to overturn Ragnarök,” spat out Loki. “What lies beyond the sea? And I’m not talking about simply circumnavigating the world. I’m talking about ignoring the three-dimensional vectors and connecting to the truly foreign. The sea divides the worlds, but there may be a similarly great ocean on the other side of that invisible boundary.”

“So they came here just fine, but repeatedly opening holes in such a short period of time could break the valve and the other ocean could pour into this world.”

One only had to think about it.

A Certain Magical Index.

Heavy Object.

The Zashiki Warashi of Intellectual Village.

A Simple Series.

The Killer Short Story Series.

They had all come from a planet named earth, but all of those earths were likely different. And what would happen if a total of five truly foreign oceans were gathered in one place? The effect would be greater than fully melting the South Pole of the planet earth. Even fleeing to the tallest mountain peak would not save one from the mouth of death.

In other words…

“An extreme rise in the ocean level. The mouth of death swallows all, hm?”

“You aren’t assuming you’re fine because you live in the heavenly world above the clouds, are you?”

“I’m not. All nine worlds are protected by Yggdrasil. If it withers away, everything comes tumbling down and I doubt Asgard is an exception.”

The world’s only land would be entirely lost and the mouth of death would devour humans, gods, and every other race alike.

“This will be just like when Odin created the nine worlds and drowned every last one of Surtr’s giant ancestors with a great flood. But this time, no one will survive. The massive amount of seawater flowing in from the truly foreign will easily ignore our world’s capacity. It’s possible it might even directly submerge the heavenly world.”

“Sea King Ægir and his queen, Rán, will survive.”

“But they cannot influence history, so their descendants will be unable to repopulate the land. We can’t expect them to copy Odin.”

“Hm.” Loki brought a hand to his chin. “I do want to change the outcome of Ragnarök, but I also want to make a more beautiful ending than the one Odin’s imagining. The mouth of death falls short on that front.”

“What are you going to do?”

“Influence things. But they will be the ones to make the final decision.”

This had to do with the worlds beyond the nine of Norse mythology, so the choice naturally went to the strangers and not the gods.

“Will they return to their truly foreign worlds or will they stay here? They have two simple options.”