Tails, whipping his tails furiously in a circle, slowly drifted back down to the floor.

"It seems there are quite a few punctured holes in the ventilation system. I'd say it was Sonic, but if it was spines, they are a little large and deep for his size."

"Unless he's currently half Terran, like we are," Knuckles added.

"So, we're automatically taller if we're Terran?" Tails asked.

"Of course. The average height on Earth, counting by the Earth measurements of feet and inches, was around five feet and six inches. On Mobius, while using the same measurements, we are only three feet tall and four inches for the average. While combined, we might be slightly smaller, but we still maintain near the average height of the planet we happen to be occupying. On the other hand, if we were in the exact same place on Mobius, we'd be more Mobian than Terran," Knuckles explained.

"If we're on Earth, why are the people called Terrans?" Tails asked.

"Because the Greek, or Roman, I can't remember, name for Earth is Tera. Therefore, an Earth person is a Terran, because it's also nicer to say than Earthling."

"Oh."

Tails watched as Knuckles punched in a security code, almost literally, and watched the door slowly slide open. If front of them was a long hall, but the hall was actually twisted to the point of being upside-down and back again as it stretched along.

Knuckles whistled. "Wow," he whispered. "I wonder if gravity is having the same problem here."

"I wouldn't doubt it..." Tails mused, thinking how fun it would be to fly downward and be going upward!

Knuckles shrugged. "We have to find Sonic and Sally anyway, so, let's go!"

Both of them traveled down the hallway, marveling at the passing windows which sometimes showed scenes from right outside Robotropolis to scenes just outside the power plant. Sometimes, it was a strange mix of both worlds, while other times, it just revealed nothing at all.

Tails shivered as he walked along. "I don't like this..." he mumbled, walking closer to Knuckles after seeing the scene of nothing again.

Knuckles cursed himself for forgetting how young Tails was. Tails always acted so much older than his age, that it just seemed reasonable to think he wouldn't get scared. Instead, Knuckles said, "You can ride on my back if you want."

Tails never had a back ride before. His hero, Sonic, had spines on his back.

"Uh...Sure, I guess..."

Knuckles leaned down to allow Tails to jump onto his back. Tails did, and held on with all his might.

"Whoa! Geez! Tails! I gotta breathe!" Knuckles gagged.

"Sorry," Tails blushed as he loosened his hold on Knuckles' neck.

After that, the walk was more peaceful. Every time Tails got scared, he just leaned his head against Knuckles' back and listened to the powerful rhythm of Knuckles' heartbeat. It held obvious strength, but it was calm and steady, and would help Tails calm down. If Knuckles wasn't scared, then Tails didn't need to be either.

But the heartbeat eventually quickened, to a faster, more frightened pace. Tails, slightly confused and a little scared, asked, "Knuckles, what's wrong?"

Knuckles didn't have to answer; there was nothing but black void ahead of them.