Down A Dark Vent

Nico de Angelo woke up to darkness.
Everything was cold. Why was it cold? Was it supposed to be?
He rolled onto his elbows, and tried to force his eyes to adjust to the dim lighting.
His throat felt sore and dry, and he could feel bruises on his ribs with every shaky breath he took.
"H-hello?" He called out horsly into the dark, his voiced echoing back at him.
He doubted he would get an answer anyways

Slowly, Nico tried to stand, he flailed for a moment before his hands found the wall that gave a metallic bang against his touch

His legs ached, and his head pounded. 
Where the hell am I?, He thought frantically. He couldn't remember anything. Not what he was doing yesterday, or the week before, or even years back. It was all a cold blank.
Nico started to panic. Had he been druged? Would that explain why he was in a dark musty tunnel with no memory, bruises and a headache the size of an elephant? Nothing made sense, and it all was starting to hurt his head even more.

Letting out a long shaky breath he didn't realize he was holding in. Nico started inching his way down the dark tunnel, keeping his hand firmly against the wall.
It stretched on for what seemed like forever.
Once in a while he would trip over ruble that was scattered around the floor, or hear strange growling noises that would echo through the halls, which would send shivers down his spine.
but other than that it was just a great walk.

A light appeared at the end of the tunnel, and Nico could start to see his surroundings better.
Metal walls stretched on all sides and above his head.
it stretched far behind him, disappearing into the dark. and in front of him, the metal walls split into a three way. That's where the light was, shining brightly and exposing the thick flakes of dust that floated around in the air.
Nico almost forgot about the pain in his legs, he clumsily ran the rest of the way, his footsteps making a faint metallic thuds with each step.

As nico approached the three way, a large air vent looking wall was placed on the left side, letting bright yellow light come through the slits. Unlike the left side, the right was just as dark as the tunnel nico had come from.

Hesitantly, nico shuffled twords the light source. The slits were about the size of his torso, give or take a few inches.

He peaked his head out the bottom opening. The brightness blinded him at first, making his eyes water.  But even as they cleared, he still wasn't sure he was seeing straight.

The first thing nico saw was carpet, or at least it looked like it. Thick, tangled gray ropes sticking out of the ground in a jumbled mess. He couldn't see much else, the vent cutting off his vision.

Acting on impulse, he slipped through the opening. Not realizing there was a small drop to the floor, he fell ungracefully onto his back with a huff. Ouch...he whimpered, wheezing a bit as his bruised ribs flared up in pain.
Forcing himself up, he finally took a look at his surroundings
And that's when he realized he should have stayed in the tunnel.

a Giant hall loomed over him, stretching as far as he could see, and towered above him with the height of a skyscraper. nico gasped at the sight, it was all making him dizzy.

what was happening to him? for the hundredth time that day he kept asking himself

And that's when he heard rythmatic booming, shaking him to his core.