After Percy Jackson gets betrayed and sucked into another dimension, he meets the mysterious Barry Allen and his group at STAR Labs, what will he do? (set after BoO an season 2 of CW's The Flash) Also on Fanfiction.net

Two different worlds collide as Percy Jackson, demigod and Harry Potter, wizard comes face-to-face after having dreams about each other. They are both in the middle of a war and could just be each other's solution to saving the world. [Set in Harry Potter's fifth year and after the Olympian war in Percy Jackson, right before The Lost Hero] WARNING: Unedited and contains lots of grammar mistakes and misspelled words. Lots of plotholes as well!

Percy Jackson's life is finally looking bright. When his mom's books take off, she decides to attend an author expo and brings her family to Central City, where they'll be staying for one week. When Percy's parents surprise him with a visit from his girlfriend, Annabeth Chase, things get even better. Which, of course, means that it all has to go downhill. Someone has their eyes on Percy. When one of the demigods gets injured, the mysterious Flash rushes in and saves them. Now both teams have a common enemy. They just have to find out who it is. *** SPOILER WARNING *** THIS FANFIC TAKES PLACE AFTER BLOOD OF OLYMPUS, THE LAST BOOK IN THE "HEROES OF OLYMPUS" SERIES. IF YOU DO NOT WANT SPOILERS CONCERNING THE SERIES, TURN BACK WHILE YOU STILL CAN, BECAUSE THIS HAS SPOILERS GALORE. ***SPOILER WARNING*** THIS FANFIC TAKES PLACE SOMETIME AFTER "THE FLASH" SEASON ONE FINALE. IF YOU'RE NOT CAUGHT UP AND DON'T WANT SPOILERS, RUN, RUN, RUN! (Sorry, had to say it. C'mon, it's the Flash.) THIS FANFIC HAS SPOILERS. A LOT OF SPOILERS. ****None of these characters are mine. All rights/credit for "Percy Jackson" / "Heroes of Olympus" go to Rick Riordan. All rights/credit for "The Flash" go to DC Comics.****

Dawn Thompson was like any other fifteen year old girl. She crushed on boys way out of her league, she hung out with her friends at the weekends and she had hobbies, for her art. However there was something that set her apart from other girls. She was a demigod. The daughter of Iris, goddess of rainbows, to be exact. Dawn hadn't started going to Camp Half-Blood yet even though she knew she was a demigod. Her father, who too was a demigod and son of Ares, forbade her to go as he thought it was too dangerous for her. Dawn thought this was stupid as Kronos had been defeated as well as Gaia. However, one night her and her father were attacked by rogue demigods and a monster. Dawn was forced to pack her bags and travel to Long Island to go to Camp Half-Blood. She was unsure whether he survived or not. On her journey she was attacked and barely made it to Camp Half-Blood alone. Somehow, she did. At Camp her life began to turn around. Despite not knowing where her father was she found a small ray of happiness. A small ray of happiness called Leo Valdez.