For the Love of Science (Book 3 The Ultimate Crossover)

Risking Everything

"Well?" I prompted. Sans sighed. "you know video games? how the 'main character' has the ability to save at any given time, or reset when they wish? all with the click of a button?" I nodded slowly. "And I assume someone can do that in real life?" Sans nodded and paused. "could. could and can are different."
"Somebody else has the ability."
"yes."
"And.. You, Flowey, and Chara think that someone is me."
"...yes.."
"How? Who had it before? How long has this been going on?" Sans sighed and closed his sockets. "determination is the key. frisk had an overwhelming amount of it, but it seems yours exceeds theirs. as for how long.. i don't even know anymore."
"Wait Frisk? Really?" He nodded. "chara used frisk, took over their soul and committed mass genocide. killed everyone. the kid broke free sometimes, but never for long. it's never been long before the next reset." It was my turn to sigh. "Stars, I'm sorry Sans." He shrugged. "it's hard to care when it's happened a million times.." He muttered. "We should talk about the machine." I hesitated and agreed. He clearly didn't want to talk about it anymore.
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I'd told Sans about the lab in Hotland and we both agreed that we'd start building there. I kept hush about the kiss. I started on the blueprints immediately, luckily I had a photographic memory and it didn't take long to finish. Actually building the thing on the other hand was much harder. It would take a lot longer. Back to being lucky, Sans was a skeleton and I was a hybrid that wasn't easily affected by heat. Thus we got to work. We both kept a closer eye out for Flowey and Chara. Knowing they were after me, after my determination and the power of reset to torture the Underground, and WD's sons further. I couldn't allow that to happen. My tail flicked back and forth in agitation. I wanted to be with WD. I wanted him here, now. I was more scared then I let on. Something wanted me to murder. WD could make it better, somehow. I guess that just how it was with love. One can be comforted by their love, even against the worst odds. "mari? you ok? you're tails goin a bit haywire."
"Yeah sorry. Just agitated."
"...not just about the machine."
"..."
"thought so.. i want my dad back as much as you, but it takes time. you're not much of a scientist if ya ain't patient." i couldn't help but laugh. "True, Sans, true. But hasn't your father ever been impatient?"
"heh. guess you got me there."
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A month. No activity for a month. The machine was once more almost done, but we were more careful and vigilant now, more than ever since this is when they attacked last time. Not a vine in sight. That worried me more than them attacking. That meant they were planning something. Something that I wasn't sure if I beat. "done."
"Hm?"
"done." He looked at me. "it's done. did you see anything?" I shook my head. "Not a leaf." I was still searching. "do you wanna..?" I shook my head again. "No. It's your father. You shou-" I paused at a strong presence. I'd spread ink around the lab and a bit around the entrance and somebody just came into the zone. "mari?"
"Turn it on. I'll keep our company busy."
"wait wha-" I dropped through an ink portal, appearing behind Flowey and Chara. I lashed my tail at them. Flowey ducked away, but I did catch Chara's arm who cried out in pain, shocking Flowey and the ghost themself. "How can you hurt me?"
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Sans POV

"company? they're here? how'd she know?" Questions shot through my skull, that hybrid was one big mystery, but I had more pressing matters than finding out more about her. If they really were here, they were trying to claim her soul and stop the machine. I couldn't stop them, even with Mari's help, but with dad.. It could brighten our odds. I pressed the button and the machine whirred to life. The atmosphere of the building grew heavier.. Darker. Towards the center of the lab, the air started to distort a black, thin line. A ripping sort of sound could be heard as the line thickened and bled into a black circular mass. I watched in wide- socketed wonder as something, a hand with a hole in the palm, came through the black. It groped for something to grab, anything. I summoned a blaster and grabbed its muzzle, pulling. Soon his entire arm was out along with his other hand, who also grabbed the blaster. Soon his arms, head and torso was out and he kinda half pulled, half flopped out of the mass. As soon as he touched the ground, I stopped the machine, the mass swirling out of existence. I didn't watch though. I ran to him and embraced him. I couldn't believe it. I'd done it. We'd done it! He was free! "Sans.." He mumbled, seemingly disoriented. "yeah.. im here."
"Wheres.. Where's Marionette?" Crap that's right! "fighting." I shot up. "fighting flowey and chara so you could get you out! we have ta help!" Dad was struggling to his feet now, he seemed determined to do so, despite the disorientation. He grunted and stumbled to the front, I helped him. This was bad. I didn't think he'd be this affected. He wouldn't be able to help in this state. We made it out and boy.. It was one heck of a show. She dodged and fought with ease. Her tail seemed to be her main weapon other than her fists. She used those portals to slip out of tight spots. It was just amazing. Dad looked impressed too. With a hint of something else.. Worry. There was no doubt in my mind that they were a thing and honestly.. I didn't mind. Always wondered what I'd be like.. To have a mother. Then she noticed us. That moment of distraction was a BIG mistake.