A/n: Inspired by faragonart's HTTYD/Portal crossover art, and the conversations of the chat room, we have here why no one would want Hiccup as a test subject.

Hiccup woke feeling groggy, and was immediately taken aback by the bright lights and strange sounds surrounding him.

"What the-" he sat up, slowly, taking in the small clear room he seemed to be stuck in. Glancing down, he noticed that his own prosthetic was gone, replaced with a much sleeker, thinner appendage. His flight suit, too, was gone. Instead, he seemed to be wearing a brightly colored suit of some kind. Standing, a bit unsteadily on this new leg, the pulled forward the collar. Underneath the strange garment was a thinner, lighter shirt with very little sleeve. He rolled the brightly colored one piece down to his hips, tying the arms into a loose knot as he walked the perimeter of his room.

"Well," he muttered to himself, tracing the walls with his fingertips. "This is new…"

A voice startled him from his ponderings.

"Hello, and again, welcome to the Aperture Science computer-aided enrichment center. We hope your brief detention in the relaxation vault has been a pleasant one."

"Umm… yeah, sure, but where am-"

"Your specimen has been processed, and we are now ready to begin the test proper."

"What test are you-"

"Before we start, however, keep in mind that although fun and learning are the primary goals of all enrichment center activities, serious injury may occur. For your own safety, and the safety of others, please refrain from touching…"

"Where am I?" Hiccup interrupted, finally cutting of the strange voice. "And where are you?"

"You are in relaxation vault number 4709 in the Aperture Science computer-aided enrichment center. You have been selected for the testing of-"

"Tests?" Hiccup asked, turning slowly, trying to place the voice.

"Tests. Was I unclear in my use of the word? You have been selected for the preliminary testing of the Aperture Science Portal Gun-"

"Portal gun? Is that anything like a Dragon Eye? Where are you?" He asked again.

"I am everywhere. Please, refrain from asking further questions until the instructions have been completed. My name is Glad0s, and I am a Genetic Lifeform and Disk Operating System. I am here to supervise you in your testing of the Aperture Science Portal Gun-"

"Supervise me? How can you supervise me if I can't even see you?"

"Your vision is irrelevant. I can see you. Now if I may please continue? Step forward. The door will open in 3...2...1."

Hiccup waited as the wall of his room somehow slid open, revealing an exit. He cautiously made his way out of the small enclosed space and into a bigger room, still taking in his surroundings eagerly. There were mechanics and systems at play that he'd never even dreamed of.

"If you will step forward," Glad0s continued, "you will be presented with your portal gun, your main tool and resource during our testi-"

"Woah!" Hiccup exclaimed as a pedestal rose from the floor in front of him. Perched upon it was a sleek and powerful looking device. He eagerly took it up, turning it this way and that. "What does it do? Is it a weapon? Some sort of hunting device?" He shook it slightly, running his fingertips over the smooth white surface, searching for seams and crevices.

"That is a portal gun. You will use it to aid you during the duration of the tests by opening travel portals where you deem necessary. It is a highly sophisticated tool, and can be activated by pulling the small trigger under the-please do not point it directly at yourself."

Hiccup quickly turned the portal gun away from his face and toward the wall. "Pull the trigger, eh? Just like a crossbow?" And he did. A blue light circled what appeared to be a hole in the wall, a hole that he had somehow created with this "portal gun". "So it is a weapon, then?"

"No," the voice said, anger tinting it's strange quality. "It's prime directive is not as a weapon, but if you are not careful, you are going to injure yourself before the tests begin. If you please, the calibration is very sensitive. It wouldn't do to have you ruin the test field before we've begun the test proper. Now, if you pull the trigger a second time-"

"Will it get rid of the first hole?" Hiccup asked, aiming again at the hole in the wall and pulling the trigger a second time. Rather than removing the first hole, a second, orange rimmed hole appeared just to the left of the first.

"It will create your portal transport. Stepping through one of these portals will direct you through the other and out onto the other side. With this method of travel, you will complete the series of tests we have prepared for you-"

"Excellent!" Hiccup exclaimed, his excitement over the new machine taking over. "How did you make this? This doesn't look like any material I've ever seen before? What powers it? Did you have to-"

"The instructions will reveal all you need to know."

"I bet… if I aimed this thing just right, and if I had some rigid wiring, I could rig this suit into some kind of glider wings… and if I could time it just right, this could be a great way to test out new prototypes of the flight suit!"

"I do not think," Glad0s interrupted, "that you understand the gravity of the situation. These tests can be extremely dangerous if not treated with the utmost respect and consideration. You may fall-"

"Cool."

"You may get burned-"

"Ehh, not the first time."

"You may lose limbs-"

"Too late," he said, balancing on his good leg as he stuck his false one out slightly, still enthralled with the portal gun.

"On second thought, new information suggests that you are not an optimal test subject at this time. The exit is through the door on your right and down the stairs. Thank you for your time at Aperture Sci-"

"What does that do?!"

"Get out."