Chaos (The Ultimate Crossover)

Nightmare

It has been three days. Three days that had been the beginning of the end. I felt restless. Nervous. It was the end. Not even Sebastian's attempt was this dangerous. The Downworlders have been saying that Olympus had fallen. Never in my life have I been this worried. It was the apocalypse. I got out of the shower only to find a surprise unwrapped in bed. My beutuful girlfriend Clary. She was an angel. An angel with fire hair. She was looking at me with the same eyes she looks at me when I don't eat.
"What's wrong?" asked Clary walking towards me. My heart began to race. She was perfection.
"Nothing" I lied.
"You're lying" she noted. How she knew it will always remain a mystery. "What's really bothering you?"
"Remeber what the warlock said? That Olympus has fallen? Well that keeps bothering me." I replied.
"But Olympus isn't real, is it?" she asked.
"Yes, it is. A year or two ago, when we went to San Francisco for our honeymoon and we stumbled across a demon, I told you to go and thats when it all happened. I saw a guy who came slashing and slaying. He didn't look like a shadowhunter. He didn't wield a seraph blade or something similar. Instead it was just a sword. A bronze sword.
"I asked him his name. He told me he was Percy Jackson. I asked him what was he. He said that he was a demigod. A son of a god and a mortal. At first I was dumbstruck, but then it hit me. Hotch told me once that all myths were real. I told you that too, remember? Anyway, he said he was the son of Poseidon.
"That's when I began to dwell on Downworld for answers. I began asking around. Until someone responded. He was tall, very tall. He told me everything about the gods and demigods. That they settled in Manhattan, that they were more than the greeks. There were egyptian, aztec, nordic, etc.. That's when it happened."
"What happened?"
"Olympus fell. The light atop the Empire state building vanished. It was covered in glamour. I saw how 14 people just fell from the sky."
"By the Angel! That's horrible!" Just then, a knock was heard from downstairs. Clary and I grabbed our seraph blades and ran downstairs to open the door. As we grew closer the door banged harder and harder. And it stopped. I turned to face Clary. She understood. I ran faster and opened the door to the Institute. There was a note in the door. "Olympus has fallen. Chaos is rising. The pit will rise."

The road to his house was not that long. In fact we arrived in 20 minutes by motorcycle. I pressed the intercome labeled "Jackson".
"Yeah?" the receiver said.
"It's me, Jace Herondale" I replied.
"Jace? What are you doing here? People will see you! Come on up" he said and the door buzzed. 5 minutes later, he was standing in the door frame waiting for us.
"What's the emergency?" Percy asked.
"This." I handed him the paper and the package.
"What is this? Were did you get it?"
"I thought you'd know"
"Well I don't. Shit, shit, shit, shit, shit, shit!" Right there the windows in the apartment exploded. Glass flew everywhere and it stopped. All the glass and debris was floating around. Then tornadoes of debris began to form. In the window frame, a large man stood.
"Well hello there. They say you are the most powerful one. I don't see hiw you could defeat me. Oh, sorry for not introducing myself. I am Nightmare"