"Asch! Asch, c'mon! Are you with me?"
Asch slowly opened his eyes and was met with darkness. As his vision adjusted, a face began to appear, a face identical to his own. "I see you died too. Did you at least bring Van down with you?"
Luke cocked his head and looked to the side. "Well…Yes and no."
Asch's eyes widened in rage. He jumped to his feet and grabbed Luke by the collar. "What the hell are you saying? I didn't die just for you to loose to Van!"
"You don't understand! Van is dead; it's me that's not!"
Asch's hands dropped to his sides as he stared, dumfounded, at his replica. "What? But…But how…?
"And you're alive too."
"What?" Asch turned around and shook his head. "But that's impossible! I thought…I know I died…"
"You did." Luke closed his eyes as he recalled the day's events. "I still can't get rid of the felling I got when you…"
"What the hell are you trying to say?" Asch snarled as he glared at Luke. "You're not making any sense!"
"That's because I don't really understand it myself." Luke crossed his and stared off into the darkness. All I know is that after I killed Ma— Van and released Lorelei, I started to descend into a fissure that had opened. It must have gone through the room we were trapped in, as your body fell through and I managed to catch it." Luke noticed Asch shudder at the thought of his own dead body, but he kept going. "Anyway, Lorelei appeared before me and thanked me, and I felt my body begin to disappear."
Luke paused, then looked back toward Asch. "This next part I'm not sure of. Right before Lorelei headed for the fon belt, he enveloped the both of us. Then there was this blinding light, and the next thing I know, I'm in this hole, solid, and you have a pulse."
Asch sat down. His head was spinning, and he wasn't sure how long he would have been able to stand. Was Lorelei really able to restore both his and his replica's bodies? Asch wasn't sure, but that didn't matter. The most important thing at that time was finding a way out. "Do you have any idea where we are?" Asch asked without looking up.
Luke sighed. "If I had to guess, I'd say somewhere near the core."
"The core?! What was the point in reviving me if we're in a place like this? We'll starve before we know if we're even going in the right direction!"
"Maybe not. Before Lorelei left, he said that as long as there are enough seventh fonons around, we'd remain energized. Something about fonon frequencies. Anyway, I've felt a steady stream of seventh fonons flowing through here, and I'm not hungry, even though I haven't eaten in about five hours."
"That still doesn't solve the problem of getting out of here. Give me your coat."
Luke looked confused. "Why?"
"Just do it, Replica!"
"Fine, whatever," Luke snapped. He balled up the coat and threw it at Asch. "You could stand to be a little nicer."
Asch ignored him and tore a strip of cloth off the coat.
"Hey!" Luke yelled. "That's expensive!"
"Shut up." Asch took out a large bottle of some sort of liquid and poured some on the strip. He then took out his sheath, wrapped the cloth around the opening, and stuck the end into the ground. Finally, he began chanting, "Bring all to ash and ruin…Explosion!"
The entire cavern-like area erupted in fire light, revealing several tunnels and crevices that had originally been hidden in the darkness. Then the light dispersed, leaving only a small flame upon the crude torch Asch had constructed.
"Wow," Luke said as his eyes shined in the dim fire light, "This place is a lot bigger than I thought."
Asch threw Luke's coat back to him. "Hold on to that. This torch won't last forever."
"Hey, what did you pour on that thing anyway?" Luke asked as he put his damaged coat back on.
Luke laughed. "Wait, are you saying that the stuff you put in your hair is flammable?"
Asch glared back at Luke. "Yeah. What's your point?"
Luke smiled and threw up his hands. "Damn. I wish I knew that earlier. I could have learned some fifth fonic artes, and that fight we had in Eldrant would have gone a lot faster."
"You're not funny."
Luke smirked. "Sorry, must be in the genes."
Asch ignored him and picked up his flaming sheath. He walked over to a tunnel on a far wall. "The seventh fonons seem to be flowing through here." He turned back toward Luke. "If I'm right, these are remnant memory particles trying to make it to the surface. If we follow this stream, we should be able to make it out."
Luke folded his arms with a smug look on his face. "What, so you actually want to work with me now?"
"At this point, I really don't have a choice," Asch snapped as he turned back toward the tunnel.
Luke smiled and ran up to Asch and linked arms, saying, "Alright comrade, to the exit!"
"Let go of me or I'll kill you."
"Yesh," Luke said as he backed off, "You're gonna need to lighten up or this trek is going to be unbearably long."
After that, the two walked on in silence until the flame went out.
"Dammit!" Asch yelled as darkness enveloped them. "Hey Replica, give me another piece of you coat."
Luke dropped to the ground with a sigh. "Why don't we just call it a night? I'm tired."
"If we stop now, we'll never make it out of here!"
"Well if you keep going, you're going to pass out. You've been tripping over every single little rock for the past ten minutes."
"…Fine," Asch finally said as he allowed himself to collapse, "But we leave at dawn."
"How do we know when it's dawn?"
"…Shut up and go to sleep."
Yeah, I know Luke did a crappy job of explaining what happened, but he's not very knowledgeable about this matter (What is he knowledgeable about?), so I didn't want to put him out of character. I'll explain that stuff now. The whole "We don't have to eat!" thing is little more than a plot device. I need to keep them down there for two years, and the whole starving to death thing could pose a problem. So I thought, "Hey, they're perfect isofons of the collective conscience of seventh fonons, so couldn't they live just on the energy of a lot of seventh fonons?" Sure, why not.
As for the whole "We're both alive!" thing, that'll take a bit more explaining.
The most popular end theories are that either Luke comes back alive, which makes the most sense with the story elements of the game; or that Asch comes back alive, which makes the most sense with the science elements of the game. I, however, never like to make things easy, so of course, I read between the lines and read waaaaaaay too much into different events of the game, and I have now come to the conclusion that both of them made it out alive (obviously, as the above chapter indicates). So where's my proof? Well, read on, reader!
Okay, first, we need to know a bit about "The Big Bang." Based on two conversations Jade has with Spinoza and Dist, we know these three things: The Big Bang is a theory developed by the almost-never-wrong Jade, that it is supposedly inevitable between an original and replica when they are perfect isofons of each other, and that the original's fonic and strike artes weaken as the time of the Big Bang approaches. What we don't know, however, is what the Big Bang actually is. Although it is never actually stated, what happens to Star the Cheagle is implied to be a Big Bang.
So what happened to Star? Well, the poor thing was used as a lab rat by Dist, who replicated a perfect isofon of Star. When your party first encounters Star, it has been about a month(+) since Dist started experimenting on him. At this point, Star's fonic abilities are much weaker than its replica's, even though the original is supposed to be stronger. This suggests that the process leading up to the Big Bang had already begun. In fact, the process may have begun the moment the replica was created. After about three more months(+), when the party finally lets Star out, the replica is missing. When Jade later questions Star about this, Star says that he himself had died, and after he died, he felt something warm flow into him. The next thing he knew, he was alive, and the replica was gone. To sum up: When the Big Bang occurs, the original dies. The replica then sends its life force into the original, both causing the original to revive and the replica to disappear. (Dist also says something implying that the disappearing party's memories would also be inherited, but Star never confirms this.)
We now look at Asch and Luke's case. In the Cheagle case, the original became weaker immediately, but Asch was fine for over seven years. Why is that? I believe that the answer lies with Lorelei. When people keep saying that the Big Bang needs to happen between Asch and Luke because they're perfect isofons, a lot of them seem to forget that Lorelei is also a perfect isofon of the Fabre boys. Of course, no one suggests a Big Bang involving Lorelei. (And I doubt one could have happened, considering that he shoots up into the fon belt in the end.) My thinking is that Lorelei somehow inhibited the whole Big Bang process, that his presence as a third wheel of sorts helped to ground Asch and Luke, and it kept them from merging. When Van absorbed Lorelei, however, this influence weakened. That may be why Asch started to freak out after the Absorption Gate. (He could feel his abilities decline after Lorelei was trapped.)
Now let's talk about Lorelei. We know that Lorelei is the collective conscience of the seventh fonon, the healing fonon. But what's the extent of those healing powers? Well, Van shows us that Lorelei can stabilize separating fonons (Van said that his fonons were separating when he was falling toward the core.), as well as resurrect the dead (There is no way that Sync was still alive. Even if he had survived the plummet to the core, he would have starved to death by that point.). Now, who else do we know that either died or had their fonons separating?
Fast forward to the ending. Luke just freed Lorelei, Luke is now holding Asch's body, and Lorelei is congratulating Luke for screwing over the planet's memory. I think it would have been awfully rude for Lorelei to just go, "Kthxbai!" and leave the two guys that just saved his ass to their unfortunate fates. No. Lorelei resurrected Asch (You saw the hand move, right?) and stabilized Luke, and Lorelei's renewed presence in the world kept the Big Bang from happening. The big flashy part was just the finalization of what Lorelei had done.
Of course, this is but one possible future of many. ;)
(+)These time frames are estimates I made from looking at the three dates given in the game (Beginning—Rem-Decan 23, ND2018; The Return to Baticul—Gnome-Decan 2, ND2018; Post-Absorption Gate—Gnome-Redecan 28, ND2018), and the time frame given in the Star-Jade conversation (six months). As these are just estimates, they may be off by a month or so.