After the separation Killua/Gon

laboratory X mistake

In the lab, Killua found himself trapped in a sort of cage. The cage contained a liquid, definitely not water, that caused Killua to float. If it were water, Killua would have been dead instantly. Killua tried to break free, punching and kicking at the glass, but to no avail. It was reinforced glassbulletproof glass. How strange, he thought. Things got even stranger as he looked around. It was clearly a lab; he could see several monitors and computers. On one of the screens, Killua saw a human body that looked exactly like his own.

"What the hell—"

"Oh, what excitement! The thing is awake, it's awake, wow!" said a scientist, the same man who had attacked Killua with his giant machine. Now he was wearing a lab coat and safety glasses. Killua looked at him with disgust and tried to shatter the glass with his sharp nails.

"Hey, old man, let me out of this glass cage!" Killua shouted, making sure he could be heard through the glass.

"Oh, you understand our language as well. Yes, you are different; I find that fascinating. But what if those are just programmed words?" the man mused.

"Hey, you stupid asshole, open the damn door!" Killua yelled.

"Okay, the insults aren't programmed. Wonderful, wonderful," the man said, sounding surprised. "So listen, you I don't know what you are, a shapeshifter. My name is Rick. You'd better be quiet before I hurt you or, worst case, kill you," Rick said with a creepy smile. Killua thought to himself, as if that old geezer could do anything to him.

Rick: "Just as I thought, you're one of those strange creatures. Oh, you're not getting out of here. You're something new, but definitely not a good kind of new."

Killua: "Listen, old man, I don't know who you're talking about. I'm not a creature. The creature—I killed it. I'm human."

"Yeah, yeah, they always say that," Rick replied, glancing at his computer to find clues about Killua's body.

"BAKA!!" Killua shouted through the glass, pounding on it a few more times.

Rick flipped a switch, and a darker liquid began to flow into Killua's cage. Killua screamed for a moment and then quickly fell silent. "Ha, I've just pumped a deadly poisonous liquid into him. There's some electricity in it too, which should make the pain even worse. He can try to suppress the pain all he wants; it's going to hurt, and then he'll die," Rick said.

Rick watched Killua, who was now floating and probably unconscious from all the pain. Rick had pumped too much of the dark liquid into him. He looked at the giant screen, waiting for Killua to die slowly, but then something unusual happened. The screen began to change.

Suddenly, the room began to shake violently. Chemicals spilled, and monitors and computers toppled over. What a nightmare. The electricity inside Killua started to build up, growing larger and more intense, almost enough to shatter the glass.

Rick: "Oh, shit, I need to get out of here!" But before Rick could run, the glass shattered, and all the glass objects in the room exploded into tiny fragments. Rick fell to the ground momentarily.

Killua now stood there, glaring at Rick. Before Rick could say anything, Killua ripped his heart out of his chest and whispered, "When I tell you to free me from the cage, do it, or this is what happens."

Everything was now silent. The chemicals still flowed down from the cage Killua had been trapped in. Killua looked at Rick's dead body and punched him in the face one more time. Then, Killua left the lab, but his body hurt so much that every step felt like someone was pressing a branding iron against him.

Later, Killua made it outside and began searching for Canary and Alluka.