He jumped when some unknown animal made a noise not too far away from him. He lost his footing a little because of it, steadying himself against a large tree.
Another reminder that, perhaps, he shouldn't have come here alone.
The teenager stood still, frozen to the tree, for a moment. He looked around, and he listened. Nothing. He sighed, relaxing a little bit. He had some knowledge of this place, but he was only now realizing that knowing about it and experiencing it were two vastly different things. And if he didn't have an important goal to accomplish, he most likely would have avoided this place entirely.
So with the noise gone, and the silence back, he steeled himself to continue onward. If he continued to travel through this place, he had to find some kind of color. That's what all these scientists and military folks had said, hadn't they? That there was still color out there? And he needed that color. He had to find that color and bring it back home.
As he walked, he paid more attention to his surroundings, looking up and around — but not so much looking down. So when his feet started to sink into the mud, it took him a moment to understand that it was only getting worse. By the time he'd realized what was going on, he was already about knee-deep into the mud, and the more he tried to move or pull his feet out, the more the mud would pull and try to suck him in deeper.
"U-uh-oh... Oh no..." he mumbled to himself as he tried to spread the mud apart in an attempt to free himself, but it proved to be of little help. "Oh no." He looked up, and the fear started to fester as he only saw trees and bushes and more mud all around him, but no sign of anything else. Was anyone else even in here? Who would even be here?
"H... Hello?" Regardless, he couldn't get out of this mess all on his own. Maybe if he called out, someone would hear him... eventually. "I-is anybody here? I'm... I'm stuck!" Well, at least, he wasn't sinking in deeper, but the sooner someone found him, the better.