Sole Survivor (A Percy Jackson x Undertale Fanfiction)

Chapter 4

The next day, Sans follows Leo to Bunker 9 to examine Gaster's notes.

"most of these are just plans to making the gaster blaster," Sans says, shuffling through the papers.  "these are plan designs for the core."

"What's the core?" Leo asks.

"the core is our main source of power down in the underground," Sans says.  "it's the monster's main source of electricity and heat.  it also allows us to experience weather that we wouldn't normally be able to experience cuz, ya know, we're underground.  like snow."

"That's cool, you get to experience snow everyday," Leo says.  "Back in Texas, we almost never get snow."

"oh well, i'd take living up here anyday over living underground."

"So, what else did you find?" Leo asks.

"design plans for a bunch of projects we finished a long time ago," Sans says.  "i remember helping him make this one a long time ago.  it's a unique machine that is capable of sucking determination out of a human soul and converting it into a form that can be stored."

"In soul science terms, what's determination?"

"it's a magical substance that allows humans...and monsters who can handle it...to persist after having their soul destroyed," Sans says.  "in other words, it's a way to come back from the dead."

"Whoa, so, if you with enough of this stuff, it could make somebody immortal?" Leo asks.  

"essentially, yeah," Sans says.  "it's not fun fighting against somebody with enough determination to become immortal.  just imagine it for a bit leo...

"killing your mortal enemy over and over again, hoping that they might not come back, only to be disappointed again, and again, and again, dozens of times."

"Whoaaa, hey man, I just asked a question," Leo says, flinching away from Sans a bit.

"but anyways, normal humans will never muster enough determination to come back to the world of the living after dying," Sans says, still looking through Gaster's old notes..  "monsters take the stuff even worse than humans do.  the tiniest dose of it could literally melt the strongest of us.  however, unless you have the soul capacity to, you'll melt start melting after a whole syringe of it or something as well.  and, judging based on the fact that humans haven't practiced magic for centuries, i doubt anybody has the soul capacity to take in enough determination to become immortal."

"How about enough determination to live after dying once?" Leo asks.  "Just once?"

"sure, humans can survive that without really much of a problem," Sans says.  "however, the exact dosage of determination is hard to guess.  too little and you'll be getting absolutely nowhere.  too much and you'll start melting.  it's a lot less risky to naturally collect determination, but it takes humans centuries to collect enough determination for that.  humans don't live long enough, save for a single exception."

"Exception?"

"let's talk a little more about souls," Sans lectures.  "all living entities have souls.  all souls possess a special trait.  there are 7 traits souls can possess:

"perseverance, integrity, patience, bravery, justice, kindness, and lastly, determination."

"What soul trait do I have?" Leo asks.

"can't really tell you that," Sans says.  "determining a soul trait isn't an easy task.  so anyway, only people with souls of determination are able to hold enough determination to maintain immortality.  however, there were only 2 instances of people with souls of determination.  the first was the first wizard to ever walk the earth.  the second, i mercilessly slaughtered 'til they didn't want to keep dying."