So Bizarre
The strings of the Memories created by the Spell were made out of soul essence... at least Sunny was convinced that they were. They were strings of ethereal, silver light.
The strings that Sunny himself weaved, however, were made out of shadow essence. Although they were a perfect substitute for the strings of light, they appeared entirely black. This was the reason why the weaves of the Memories he modified were like a patchwork of light and darkness.
...The weave of the Estuary Key, however, had no light at all. Every string of its vast and intricate tapestry was black, as if created out of shadow essence. It was just like the Siege Souvenir that Sunny had made and used to kill Goliath.
Sunny stared at the jagged piece of black stone, dumbfounded.
'What... what is the meaning of this?'
How could there be a Memory such as this if he had not created it?
Suddenly, there was cold sweat on his face.
'...Have I lost a part of my memories?'
Oblivion, oblivion... the answer was oblivion...
Sunny shifted, and his hand instinctively shot to the side, ready to grasp a weapon.
The Sin of Solace observed his panic with an amused smile.
A few seconds passed, then a few more. The Great River was peaceful and desolate, with not a threat in sight. Slowly, Sunny allowed himself to relax.
'Even if I somehow lost some memories, that wouldn't explain this damned Memory!'
Sunny was certain that he was not capable of creating a spellweave of such magnitude and complexity. He was nowhere near that level, as far as weaving was concerned...
Much more importantly, he knew for a fact that he was not capable of killing a Great Terror to collect six Supreme soul shards. Although, if this Memory was an artificial one, the soul shards could have come from six Great Beasts instead...
"Or six Sovereigns."
The Sin of Solace offered a suggestion with a mocking grin.
Sunny flinched, then glared at the apparition. His face was even paler than usual.
"Ha. Ha... very funny."
He was incapable of killing six Great Beasts, either. Or even one... most likely.
'So what does it mean?!'
Now, he really felt as if he was losing his mind. A Supreme Memory of the Sixth Tier appeared in his soul out of nowhere, and on top of that, it seemed to have been made from shadow essence.
It was just too bizarre!
Sunny groaned, grabbed his head and froze for a few minutes, thinking. After a while, his agitation lessened a little.
'It... it can still be explained. Even if the explanations are more than a little bit out there.'
First of all... the fact that the strings of the Estuary Key's weave were seemingly made out of shadow essence did not mean that it was Sunny who had created them. There could have been another shadow creature capable of weaving somewhere here.
In fact, Sunny had never received a Memory for killing a shadow creature. Who knew, maybe all Memories awarded for slaying shadows were like that?
So... it was still possible that somewhere in the waking world, Serpent had slain a Great Terror that had been a shadow creature once, and Sunny received the reward - which just happened to be tied to the Great River - while asleep.
Of course, it was extremely hard to believe that something like that had happened. But Sunny had been living with the [Fated] Attribute for many years now... if there was one thing he had learned, it was that he should never say never. All kinds of improbable coincidences were prone to happening to him.
There were two other explanations, as well.
One of them was that Sunny had somehow vastly improved his mastery of weaving, procured six Supreme soul shards, created the Key of the Estuary, and then forgotten all about it.
In the process, none of his other runes had changed, either - his Class, number of shadow fragments, collection of Memories, and the state of his Shadows were all the same as they had been before entering the Nightmare.
Well, that was not exactly true - one thing about him had indeed changed, and to a frightening degree. It was the Sin of Solace... the spirit of the cursed sword was entirely different from how it had been before. But that was the only discrepancy.
Nevertheless, the second explanation was even less believable than the first one. Too many things about it did not make any sense.
The third explanation had to do with the Great River, and the nature of time. Since time worked strangely in this Nightmare, it was... maybe?... possible that Sunny would create the Key of the Estuary in the future, but was somehow capable of already possessing it in the present.
He really didn't know that much about time... or rather, he knew just as much about it as any person would. Sunny was not ignorant, but time itself was like a perversion of itself here. In any case, he had no idea how it worked on the Great River. So, who was to say that something like that couldn't happen?
The third explanation was the most bizarre... and yet, it somehow sounded more plausible than the other two.
Sunny dismissed the Estuary Key and silently stared at the vast expanse of flowing water in front of him. The seven suns were slowly traveling across the blue sky.
'So, in conclusion. I have no idea how I ended up on this river instead of in the Nightmare Desert, no knowledge about what the Great River actually is, no hints about what to do to conquer the Nightmare, and no clue where the others are. And on top of that, there is a mysterious Memory in my soul, and the Sin of Solace seems to have gone through a strange transformation.'
Sunny sighed as he enjoyed the beautiful view.
"Wonderful."
The Sin of Solace glanced at him with a smile.
"I'm glad you're in a good mood."
Then, the apparition took a tentative step back and grinned.
"But, Sunny... shouldn't you be paying more attention to the surroundings in a situation like this?"
Sunny frowned for a moment, then suddenly opened his eyes wide.
He had been distracted by the barrage of weird revelations and lulled into a false sense of security by the beautiful tranquility of the Great River...
Which was why he was a second too late to sense a vast shadow rising swiftly from the depths below him.
Summoning a Memory, he cursed and jumped high into the air.
In the next moment, giant jaws tore the surface of the water on both sides of his makeshift raft and closed, turning it into thousands of sharp splinters...