I co-wrote this with my best friend, so I hope you like it! I wrote the TT parts, my friend wrote the HoO parts. I do not own Teen Titans, Heroes of Olympus, or the song I set fire to the rain.

Chapter 1: 14 heroes, 2 teams, 1 goal

"Being a hero means sacrifice… pain… strength… courage… and endurance… whatever it takes to protect the world… and stop those who want to corrupt it… Being a hero isn't easy… but sometimes we don't have a choice… forced to protect a world who doesn't even believe in you… a world which has hurt you so much… fourteen of these extraordinary souls will come together as one… to beat two who have strayed from the path of righteousness… two who have retaliated against reality… this is the story… of the Demigods… of the Titans… of the Challenge of the United."

A group of seven teenagers sat in the corner of a busy night cafe in Paris. Percy Jackson, son of Poseidon and leader of the group, surveyed the team. Jason Grace, son of Jupiter, sat with his arm around Piper McLean, daughter of Aphrodite. Leo Valdez, son of Hephaestus, was bouncing off the walls, being ADHD and having just downed a cup of coffee. Hazel Levesque, daughter of Pluto, stared blankly out the window, while her brother, Nico di Angelo, sat in a lonely corner, twisting his skull ring and quietly observing. Suddenly, Annabeth Chase, daughter of Athena, burst in. "Annabeth!" Percy said, rising. "Percy, you'd better come see this," She said, her blonde hair wind blown, eyes alight. "Come on, everyone," Percy beckoned. The half-bloods rose and followed, inquisitive expressions on their faces. They saw a (purple) beacon, pulsing atop the Eiffel Tower. "What in Hades is that?" Jason yelled. "I don't know," admitted Annabeth, "but it doesn't look good."

The six Teen Titans, along with newcomer Kole the spinner of crystal, walked down the dark, empty streets of Paris. They had left Jump City in the hands of a fellow Titan team= Titans East.

"Wow! Vacationing in Paris was a great idea!" Beast Boy, shapeshifter supreme, said as he looked at all the closed foreign stores. "We're not here on vacation Beast Boy, we're here on patrol, since there are no Titans in France," Robin, the boy wonder and team leader, coldly stated. Clinging onto his arm was Starfire, alien powerhouse and his girlfriend. Behind Robin stood Cyborg, the half man half robot, with a tour guide in his large, metallic hands.

"Come on, Robin! Lighten up!" Terra, a bender of earth, put a hand on his shoulder. 'Here we go again,' The dark mistress of magic, Raven, thought as she rolled her violet eyes under the hood of her cloak.

"Yeah, man! I mean, this is Paris! Who cares if it's 11:00 at night? I don't want a repeat of Tokyo!" Cyborg yelled into the boy's ear. Raven sighed when she suddenly noticed a bright (purple) beacon coming from the top of the Eiffel Tower. She arched an eyebrow and turned to her arguing friends.

"Uh..."

"Look, we've got Titans all over the globe, EXCEPT in Paris!"

"That ain't a reason to never go on a vacation!"

"Friends! Please stop arguing!" Starfire stepped between the two Titans while Raven kept on trying to get their attention.

"Hello? Disaster occurring?"

"Dude, superheroes need vacations too!" Beast Boy said.

"Yeah, we are just teens!" Kole spoke from behind an agitated Cyborg.

"GUYS!" Raven yelled. They turned to face the young empath with red veins popping out of their foreheads.

"What?!" She pointed a pale finger at the beacon.

"According to all the fear I'm sensing, I don't think it's just a light show." "TITANS, GO!"

Percy first sighted the beacon up close. Behind him were Annabeth, Piper, Hazel, Jason, Nico and Leo. "What's going on?" Jason asked, flipping his coin, which transformed into a lance. "I don't know, but it looks like trouble," Annabeth warned. She drew her dagger, grey eyes analyzing the scene atop the tower. Nico and Percy cursed in Ancient Greek, both unsheathing swords-Nico's was Stygian iron, and Percy's was a pen, that, when uncapped, transformed into a celestial bronze sword. Hazel and Piper followed suit, following Percy to the top of the Eiffel Tower. In the corner of his eye, he spotted seven teens, about his age, flying up towards the top of the Eiffel Tower. One had black, spiky hair, a mask, and a suit of some sort that made him look like a traffic light. He used the black and yellow cape as a glider. The tall girl above him had fiery red hair, glowing green eyes, and a purple outfit. Another one was half metal and strangely, being carried by a green pterodactyl. Next to them was a blonde and a girl with pink hair on a floating rock. The nearest one to him wore a dark cloak and a black leotard. The only feature of her he could make out was her glowing white eyes. They landed next to the half-bloods and the two leaders' eyes met. "Who-" Robin, the masked boy, began. "-are you?" Percy finished, green eyes narrowing. "We'll answer that question," two voices said. They seemed to be coming from the beacon. To the Titans and heroes alike, two figures emerged from the beacon.

"I," said the one with the wild red hair, "am Fyre." She wore a black cape with a crimson red lining, fastened at the left shoulder with a platinum epaulette. A black skirt, hemmed with the same crimson red, slanted down to the right and was fastened around the hip with two crossing leather belts. Below that was a pair of tight, black shorts. A black low-cut top matching her skirt adorned her slim torso. She also had on black, fingerless gloves and dark red combat boots, decorated with rusty chains.

"And I," said a male voice, "am Rayne." He had dark blue hair with lighter blue highlights, and wore a cloak as well. It was black with a navy blue interior, also fastened at the left shoulder with a platinum epaulette. His shirt was black with a blue lining and had a navy blue waist wrap with a long and wide, black loincloth with the same navy blue lining. His boots were dark blue and tied with chains. The Teen Titans and Heroes of Olympus gasped in shock. They stood dumbstruck at the strange pair. "We have heard legends of heroic demigods, also known as the Heroes of Olympus, and have come to test our strength against them," explained Rayne. "We have also heard tales of meta-human teenagers, known as the Teen Titans, and have come to see them prove their worth," said Fyre, casting a wary eye over the group.

"Game on!" Rayne and Fyre launched at the two teams of heroes. "Titans, go!" "For Olympus!" Robin pulled a bird-a-rang out of his utility belt, which transformed into a sword. The two leaders pointed their swords at Fyre and Rayne while yelling their battle cry. Rayne attacked first, launching himself at Percy. Their swords met sending sparks. Percy stumbled from the force of the blow. 'Gods of Olympus, he's strong!' thought Percy. Fyre attacked the tall girl known as Starfire, who countered the blow with her starbolts. "Hey, hothead! Over here!" Beast Boy, the once green pterodactyl, waved his hands in the air. Fyre went after him while Nico knelt, placing a hand on the ground. He chanted a few words in Ancient Greek, and the ground cracked open. Two skeletal warriors emerged from the chasm, one medieval knight and one Viking, swinging their weapons. Nico gave them direct orders, and they attacked Rayne.

Meanwhile, Terra, the blonde on the floating rock, threw multiple boulders with yellow auras at Fyre, who blocked them with her double fiery blades. Leo had his hands lit on fire, running at Rayne like a maniac on steroids. The son of Hephaestus touched the villain's billowing cloak, singing, "And I set fire, to the Rayne..." Hazel rolled her golden eyes, taking a stab at Rayne as he extinguished Leo's flame. He blocked her blow with uncanny agility and speed.

"Azarath Metrion Zinthos!" Raven, the girl with the dark cloak, blasted Fyre's double swords out of her hands. She started to throw discs of her black energy at the new villainess. Fyre jumped up and used the discs as stepping stones. Once she got close enough, she round-house-kicked raven in the head, causing her to fall unconscious. Kole, the pink haired one, hopped over her and she swung an arm at Fyre, aiming several shards of crystal at her. The shards sunk deep into Fyre's skin, but she held in the agonizing scream that would have shattered eardrums of Persians within 5 miles.

Jason swung his lance in a complicated pattern, parrying Rayne's strikes. He yelled in Latin, summoning lightning from the sky. Rayne narrowly dodged the bolt, striking at Jason with pure malice. Down went the son of the sky god, bleeding. Piper McLean, the Native-American girl, and Annabeth charged at Rayne, their beautiful faces marred with terrible snarls. Despite Rayne's phenomenal battle skills, Piper managed to nick him on the leg, and Annabeth delivered a gash on the forearm. "That," Piper said, "was for our boyfriends."

Cyborg aimed his cybernetic cannon at Fyre, who was busy fighting Terra and screamed. "BOO-YAH! TAKE THAT, HOTHEAD!" He fired (pun intended) at the villainess. "Wow, your arms are thick," Fyre commented, dodging the cannon. "Yeah? The only thick thing here is your head!" he yelled, firing again.

Robin and Percy stood back to back as Rayne and Fyre drew closer and closer. "And to think, I thought I was having a bad hair day!" Robin said, descrying Fyre's wild hair. "Dude, you think you have hair issues? You should see me in the morning." Rayne and Percy's swords clashed once again. Before Fyre could reach him, Robin switched his bird-a-rang/sword for three freeze discs. He tossed them at the ground under Fyre and once the smoke cleared, she was frozen in ice. He picked up his bird-a-rang/sword and jumped up high in the air, ready to crush the block of ice into thousands of tiny pieces, but instead, she broke out and gave him a harsh blow to the stomach, causing him to fall on to the ground and holding his stomach. Rayne saw an opening when Percy was distracted and pushed him away.

"Enough!" Rayne and Fyre called in unison. "Unimpressive," Fyre mused, polishing her swords with her cloak. "Agreed. Beware, Titans and Heroes, of Rayne, the son of the sky, sea, and Underworld gods, and of Fyre, master assassin and swords woman. We shall meet again." With that, the strange pair jumped off the Tower, vanishing into the night.

After the two villains left, Robin looked at Percy. "Anyway, I'm Robin, the team leader, this is Starfire, Beast Boy, Cyborg, Terra, Kole, and Raven," he said. "We're the Teen Titans." Percy shook hands with Robin. "I'm Percy Jackson, son of Poseidon, this is Annabeth Chase, daughter of Athena and my girlfriend, the guy who's jumping around like a jellybean is Leo Valdez, son of Hephaestus, Jason Grace, son of Jupiter, Piper McLean, daughter of Aphrodite, Hazel Levesque, daughter of Pluto, and Nico di Angelo, son of Hades. He's also goth, " Robin asked, "So, who were those guys?" "No idea," said Percy. "Hey, dudes, I'm like, super tired," Beast Boy said, yawning. "Fighting takes a ton out of me." Piper pointed to a hotel across the street. "Over there. I'm sure we could stay there for the night," she said. "Does anyone here know French?" asked Kole. "I do," said Piper. Kole arched a brow. "French is the language of love. My mom's Aphrodite, goddess of love," Piper explained. "Race ya there!" Cyborg said. They took off toward the hotel, leaving the two goths behind. Raven and Nico glanced at each other and said in unison, "Pointless." They strode off toward their friends.

Hope you liked it! If we made any mistakes, please tell us! xXarcherXx, out!